Jaguar XK8 - ZF6HP26 Transmission - Critical Intel!
#1
06-26-2018, 03:41 PM
Jaguar XK8 - ZF6HP26 Transmission - Critical Intel!
Hi Lads,
If you do a search on Razorboy threads, you will see plenty on my transmission issues.
I am being dramatic on the title to make certain that anyone who is encountering issues such as I have - at least takes a look at this and maybe save many thousands of dollars.
Going to bullet a lot of this to speed up the read for you too:
1) Bought 2003 Jag XK8 couple of years ago with 120k on the clock. Needed work but seemed to drive decent from SoCal to Las Vegas
2) With 120k on the clock, I decided to do the transmission service and I had a little bump going from 2nd to 1st like pulling up to Stop signs.
3) Shortly after transmission service using Mercon SP and new filter, I went on the hwy and in a kickdown from 6th to 5th saw my first transmission fault indicator.
4) Emptied and refilled transmission again thinking I needed more old fluid out. The stuff that came out originally was pretty dark
5) 2nd to 1st bump got better but it was obvious something wasn't right. Continued to throw transmission faults that would reset after the car sat for a few minutes
6) Purchased JLR software from Britain after research and used it to clear the adaptive memory and start over. Also got the codes with the primary ones being gear ratio faults and output speed sensor faults
7) Had basically convinced myself that the issue was either the valve body or the guts of the transmission itself but I saw no particles to speak of in the transmission fluid or on the magnets in the filter.
8) Continued to struggle with the transmission but seemed to get away with using the J-Gate to shift for a while. Finally just parked the car in preparation for what to do next
9) Used the car here and there for limited runs until the day came where everything went ape-****. Transmission fault, DSC and ABS fault, limp home mode deluxe
10) Discovered intel on the seals between the valve body and the transmission as a possible problem so I ordered them in and cracked the pan off again
11) Pulled the valve body and decided to take it local and have it tested by a ZF certified valve body specialist. He called and said that the E-clutch circuit should be providing about 200psi of pressure - it was producing nothing - I jumped for joy.
12) Coughed up 1000 dollars to have the valve body completely rebuilt with all original ZF parts. Figured I couldn't go wrong and if I needed to replace the transmission, I would have a fresh valve body to go with it.
13) During all of this time, I had a rattle in the drivers rear corner. I thought it was a loose shield or maybe a suspension bushing but ignored it as I had bigger fish to fry with the transmission
14) After getting the fresh valve body back in, I took the car for a test drive. It was different a bit but it didn't take long before the faults happened again and I now had a wheel speed sensor fault on the drivers rear?
15) Decided the easiest thing to do was to swap the rear sensors around which I did and got another fault. Same wheel so I knew it wasn't the sensor and the JLR live data confirmed that all sensors were generating like signal
16) Don't really know what triggered it but I had an epiphany and jack the rear of the car up and moved the rear wheel. I had a LOT of play in the rear wheel bearing on the driver side and a healthy amount of play on the passenger side rear as well. Fronts were solid.
17) I started pondering about this and the transmission faults but especially the DSC and ABS faults as the wheel bearing issue would most certainly put the phonic wheels out of alignment with the sensors. Ordered new wheel bearing kits for both sides
18) Did the passenger side first which was pretty straightforward but the driver side was in rough shape. I had to use a 3 lb sledge and a drift to knock the hubs out of the very damaged inner bearing and the outer bearing wasn't much healthier. Got it all back together and dropped the car to the deck for the first run.
I went out on the test drive with absolutely no expectations other than maybe this was what was making the rattling noise in the rear and I was right. The rattle had completely disappeared BUT so had all of the transmission issues!! I had considered that this might be a very slight possibility not knowing exactly the logic behind the sensors, ECU and TCM.
Now hindsight is 20/20 but I scoured the internet for months and asked hundreds of questions even on this site and from gurus and not one person brought up the possibility that the issue could have been wheel bearings but yet that's exactly what has caused all of my issues with the transmission for so long. I have gone on three 30 mile + runs and have not witnessed a single shift issue, no faults and even the 2nd to 1st bump is non-existent. The transmission feels as though it is all brand new again and believe me when I say that this is not a statement of a mild improvement, this is absolutely cured of its issues. I have put nearly 100 miles on the car since yesterday and have witnessed zero issues and before the problems would have started before I got to the end of my street.
So here is my breakdown of the problem and the cure that I discovered:
All four wheel speed sensors feed data back to the computers for various reasons. What the direct correlation is between them and the TCM is not exactly clear but obviously there is a relationship
I assume that there is enough backup / averaging in the computers to compensate for a single bad wheel speed sensor but what about two of them? Meaning both rears not sending consistent signals? The computer sees the sensors working because they were but the sensors are obviously out of physical alignment to the phonic wheels and because there is play in the bearings, the wheel jumping up and down while driving may be presenting some very messed up data that the computers cannot resolve which causes errors which leads to assumptions by the computer about what is wrong. It also means the inaccurate data screws with the TCM and because of that causes inadvertent shift activity leading to other codes and ultimately transmission faults. In hindsight, the DSC and ABS faults were clear indicators that a wheel bearing or sensor issue was in play but how much that mattered to the TCM was unclear to me until now. Turns out it is VERY important
Now I sit and wonder a few things:
1) Is this a forever fix? I haven't really put my boot into it yet but simply drove normally all the way up to 80mph on the freeway without a glitch. Before as I said I couldn't get to the end of my street without some weird buck or shift. I will hold out final judgement for a few days as the transmission may have suffered internal damage because of this issue but again I say that this fix is not subtle - its an astonishing change
2) I wonder how many ZF transmissions have been swapped out over the years because of a misdiagnosis on this issue. I was days away from buying a rebuilt transmission and getting into a lot of labor to swap it out.
Guys, look for my threads and see how long I dealt with this and how much effort I put into finding the REAL fix.
I simply advise anyone throwing faults on their transmission to do this before you try anything else. Just jack up each corner of the car and placing your hand on the top and bottom of the tire, rock the wheel in and out. You should only feel a very slight amount of play in the wheel bearing. If there is any more that half a millimeter lets say, you should start by having the offending wheel bearings replace. Do not and I repeat do not run to the nearest dealership for a new transmission until you completely, 100% certain that all wheel bearings and all wheel speed sensors are in perfect health.
For me this journey has ended:
Gear Ratio Faults - gone
Transmission output speed sensor faults - gone
Wheel speed sensor faults - gone
Weird shifts and bucking sometimes between gears - gone
2nd to 1st gear bump - gone
RPM flaring between 3-4-5 shifts - gone
DSC and ABS warnings - gone
thousands of dollars for a transmission - still in my pocket
Car now hauls ***
I hope someone out there gets the most out of this thread. Although its too late to help me, I hope it saves someones *** one day so it was worth writing every single word.
Possibly my biggest forum contribution ever!
If you do a search on Razorboy threads, you will see plenty on my transmission issues.
I am being dramatic on the title to make certain that anyone who is encountering issues such as I have - at least takes a look at this and maybe save many thousands of dollars.
Going to bullet a lot of this to speed up the read for you too:
1) Bought 2003 Jag XK8 couple of years ago with 120k on the clock. Needed work but seemed to drive decent from SoCal to Las Vegas
2) With 120k on the clock, I decided to do the transmission service and I had a little bump going from 2nd to 1st like pulling up to Stop signs.
3) Shortly after transmission service using Mercon SP and new filter, I went on the hwy and in a kickdown from 6th to 5th saw my first transmission fault indicator.
4) Emptied and refilled transmission again thinking I needed more old fluid out. The stuff that came out originally was pretty dark
5) 2nd to 1st bump got better but it was obvious something wasn't right. Continued to throw transmission faults that would reset after the car sat for a few minutes
6) Purchased JLR software from Britain after research and used it to clear the adaptive memory and start over. Also got the codes with the primary ones being gear ratio faults and output speed sensor faults
7) Had basically convinced myself that the issue was either the valve body or the guts of the transmission itself but I saw no particles to speak of in the transmission fluid or on the magnets in the filter.
8) Continued to struggle with the transmission but seemed to get away with using the J-Gate to shift for a while. Finally just parked the car in preparation for what to do next
9) Used the car here and there for limited runs until the day came where everything went ape-****. Transmission fault, DSC and ABS fault, limp home mode deluxe
10) Discovered intel on the seals between the valve body and the transmission as a possible problem so I ordered them in and cracked the pan off again
11) Pulled the valve body and decided to take it local and have it tested by a ZF certified valve body specialist. He called and said that the E-clutch circuit should be providing about 200psi of pressure - it was producing nothing - I jumped for joy.
12) Coughed up 1000 dollars to have the valve body completely rebuilt with all original ZF parts. Figured I couldn't go wrong and if I needed to replace the transmission, I would have a fresh valve body to go with it.
13) During all of this time, I had a rattle in the drivers rear corner. I thought it was a loose shield or maybe a suspension bushing but ignored it as I had bigger fish to fry with the transmission
14) After getting the fresh valve body back in, I took the car for a test drive. It was different a bit but it didn't take long before the faults happened again and I now had a wheel speed sensor fault on the drivers rear?
15) Decided the easiest thing to do was to swap the rear sensors around which I did and got another fault. Same wheel so I knew it wasn't the sensor and the JLR live data confirmed that all sensors were generating like signal
16) Don't really know what triggered it but I had an epiphany and jack the rear of the car up and moved the rear wheel. I had a LOT of play in the rear wheel bearing on the driver side and a healthy amount of play on the passenger side rear as well. Fronts were solid.
17) I started pondering about this and the transmission faults but especially the DSC and ABS faults as the wheel bearing issue would most certainly put the phonic wheels out of alignment with the sensors. Ordered new wheel bearing kits for both sides
18) Did the passenger side first which was pretty straightforward but the driver side was in rough shape. I had to use a 3 lb sledge and a drift to knock the hubs out of the very damaged inner bearing and the outer bearing wasn't much healthier. Got it all back together and dropped the car to the deck for the first run.
I went out on the test drive with absolutely no expectations other than maybe this was what was making the rattling noise in the rear and I was right. The rattle had completely disappeared BUT so had all of the transmission issues!! I had considered that this might be a very slight possibility not knowing exactly the logic behind the sensors, ECU and TCM.
Now hindsight is 20/20 but I scoured the internet for months and asked hundreds of questions even on this site and from gurus and not one person brought up the possibility that the issue could have been wheel bearings but yet that's exactly what has caused all of my issues with the transmission for so long. I have gone on three 30 mile + runs and have not witnessed a single shift issue, no faults and even the 2nd to 1st bump is non-existent. The transmission feels as though it is all brand new again and believe me when I say that this is not a statement of a mild improvement, this is absolutely cured of its issues. I have put nearly 100 miles on the car since yesterday and have witnessed zero issues and before the problems would have started before I got to the end of my street.
So here is my breakdown of the problem and the cure that I discovered:
All four wheel speed sensors feed data back to the computers for various reasons. What the direct correlation is between them and the TCM is not exactly clear but obviously there is a relationship
I assume that there is enough backup / averaging in the computers to compensate for a single bad wheel speed sensor but what about two of them? Meaning both rears not sending consistent signals? The computer sees the sensors working because they were but the sensors are obviously out of physical alignment to the phonic wheels and because there is play in the bearings, the wheel jumping up and down while driving may be presenting some very messed up data that the computers cannot resolve which causes errors which leads to assumptions by the computer about what is wrong. It also means the inaccurate data screws with the TCM and because of that causes inadvertent shift activity leading to other codes and ultimately transmission faults. In hindsight, the DSC and ABS faults were clear indicators that a wheel bearing or sensor issue was in play but how much that mattered to the TCM was unclear to me until now. Turns out it is VERY important
Now I sit and wonder a few things:
1) Is this a forever fix? I haven't really put my boot into it yet but simply drove normally all the way up to 80mph on the freeway without a glitch. Before as I said I couldn't get to the end of my street without some weird buck or shift. I will hold out final judgement for a few days as the transmission may have suffered internal damage because of this issue but again I say that this fix is not subtle - its an astonishing change
2) I wonder how many ZF transmissions have been swapped out over the years because of a misdiagnosis on this issue. I was days away from buying a rebuilt transmission and getting into a lot of labor to swap it out.
Guys, look for my threads and see how long I dealt with this and how much effort I put into finding the REAL fix.
I simply advise anyone throwing faults on their transmission to do this before you try anything else. Just jack up each corner of the car and placing your hand on the top and bottom of the tire, rock the wheel in and out. You should only feel a very slight amount of play in the wheel bearing. If there is any more that half a millimeter lets say, you should start by having the offending wheel bearings replace. Do not and I repeat do not run to the nearest dealership for a new transmission until you completely, 100% certain that all wheel bearings and all wheel speed sensors are in perfect health.
For me this journey has ended:
Gear Ratio Faults - gone
Transmission output speed sensor faults - gone
Wheel speed sensor faults - gone
Weird shifts and bucking sometimes between gears - gone
2nd to 1st gear bump - gone
RPM flaring between 3-4-5 shifts - gone
DSC and ABS warnings - gone
thousands of dollars for a transmission - still in my pocket
Car now hauls ***
I hope someone out there gets the most out of this thread. Although its too late to help me, I hope it saves someones *** one day so it was worth writing every single word.
Possibly my biggest forum contribution ever!
#4
06-27-2018, 03:08 AM
Veteran Member
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#5
06-27-2018, 06:33 AM
Veteran Member
Well done. As we know, these cars are essentially rolling computers and even the most inobtrusive glitch can set off faults and codes that may or may not be accurate....
There are a few instances here on the forum where owners have unfortunately had their ZF units rebuilt or replaced when all that was actually required was a new battery. Tremendously expensive mistakes can be made when owners do not methodically search for all potential causes before giving up on the transmission. Kudos to you for eventually discovering what certainly appears to be your primary issue....
There are a few instances here on the forum where owners have unfortunately had their ZF units rebuilt or replaced when all that was actually required was a new battery. Tremendously expensive mistakes can be made when owners do not methodically search for all potential causes before giving up on the transmission. Kudos to you for eventually discovering what certainly appears to be your primary issue....
#6
06-27-2018, 01:56 PM
I think this thread or at least a new one with an easy to understand title should be made a sticky!
I say that because I have tried to share the same info several times yet razorboy never saw it.
from a posting I made last spring (2017)
https://www.jaguarforums.com/forum/x...solved-179538/
I say that because I have tried to share the same info several times yet razorboy never saw it.
from a posting I made last spring (2017)
https://www.jaguarforums.com/forum/x...solved-179538/
Many fault messages –RESOLVEDI hope!
My 2005 XK8 conv started having a no abs fault last fall. I drove the car another 3500 miles before ripping into it.
It started like this:
abs fault then led to
no dsc then
no cruise then
tranny making weird downshifts between 15~25 miles per hour then
the abs applying the brakes occasionally then
gear box fault then
combinations of all of the above.
Story made short…I replaced the left rear wheel bearings and have driven the car (knock on the wooden dash) 850 miles without any fault messages, weird downshifts, noises…nothing.
What a nice car it is to drive when things work properly.
BTW, the rear bearings were so worn that I had 10~15 mm of 12-6 movement. The tip off was that when I went into a turn I would hear the click, click, click and that was followed by a no abs fault message. It looks as if the reluctor was actually moving out of the range of the sensor.
I followed up this spring stating I now had 4500 miles without further issues.
in another thread which was missed,
So, how do we make this info more easily searchable?
wj
My 2005 XK8 conv started having a no abs fault last fall. I drove the car another 3500 miles before ripping into it.
It started like this:
abs fault then led to
no dsc then
no cruise then
tranny making weird downshifts between 15~25 miles per hour then
the abs applying the brakes occasionally then
gear box fault then
combinations of all of the above.
Story made short…I replaced the left rear wheel bearings and have driven the car (knock on the wooden dash) 850 miles without any fault messages, weird downshifts, noises…nothing.
What a nice car it is to drive when things work properly.
BTW, the rear bearings were so worn that I had 10~15 mm of 12-6 movement. The tip off was that when I went into a turn I would hear the click, click, click and that was followed by a no abs fault message. It looks as if the reluctor was actually moving out of the range of the sensor.
I followed up this spring stating I now had 4500 miles without further issues.
in another thread which was missed,
So, how do we make this info more easily searchable?
wj
The following 4 users liked this post by wymjym:
#7
06-27-2018, 02:35 PM
Veteran Member
Trending Topics
#8
06-29-2018, 09:57 AM
Well I am several days in now and all seems well.
I have a slight flaring in 3rd but I attribute that to a older worn transmission that has seen some issues. All other gears are working as they should.
Yesterday I reset the adaptive memory so I am now smoothing out the shifts. Figured with such messed up wheel speed data being sent to the TCM, the car had learned some bad shifting habits and I have the JLR software.
There is a TCM firmware upgrade available in the JLR software but it scares the crap out of me and I have heard some horror stories of people bricking their TCM trying to update the firmware.
I have reset the adaptive a number of times and although very slow process on the 2003 MY, it always completes with no issues. I always have the car on the battery charger when I use the software and the laptop is always plugged into AC power with my power settings set to always on. No screen-saver, etc. Maybe later when I am bored of a normally running car I will take a stab at the firmware upgrade
I will be honest - the search function on this site is horrible. I routinely do Google searches on various Jag topics like transmissions and Google will ultimately point me to many posts on the topic I have chosen to search. If I do the same search criteria here, I get a couple of pages of random posts with many not having anything to do with the topic I was searching for to begin with. It is frustrating and time consuming and I agree with the poster, we need to find a better way of pinning these critical posts. It could save a Jag owner many thousands of dollars. I talked to a few different people about my transmission issues and almost everyone said that my transmission was toast. I even spoke to one shop that said they don't bother to test anything with the symptoms I described, they just go ahead and swap the transmission as it is less labor to do that than to troubleshoot other potential causes. Wow -
So I can say with complete confidence that this was indeed the issue I suffered from. The JLR software shows no more stored or pending codes to do with transmission and although I am always happier shifting with the J-Gate, the D position works fine and only has the slight flare through 3rd gear. As a reward to myself and the car for finally getting to the bottom of this, I went ahead and purchased all new brakes for the rear with vented, cross-drilled rotors, pads and even new parking brake components. Then its off to have an alignment done and after that I am just going to drive it for a while. It's been a bit of a journey getting the car to the point where it is and there is still more to do but nothing that parks it like the transmission issues did. Persistence pays off in the end
I have a slight flaring in 3rd but I attribute that to a older worn transmission that has seen some issues. All other gears are working as they should.
Yesterday I reset the adaptive memory so I am now smoothing out the shifts. Figured with such messed up wheel speed data being sent to the TCM, the car had learned some bad shifting habits and I have the JLR software.
There is a TCM firmware upgrade available in the JLR software but it scares the crap out of me and I have heard some horror stories of people bricking their TCM trying to update the firmware.
I have reset the adaptive a number of times and although very slow process on the 2003 MY, it always completes with no issues. I always have the car on the battery charger when I use the software and the laptop is always plugged into AC power with my power settings set to always on. No screen-saver, etc. Maybe later when I am bored of a normally running car I will take a stab at the firmware upgrade
I will be honest - the search function on this site is horrible. I routinely do Google searches on various Jag topics like transmissions and Google will ultimately point me to many posts on the topic I have chosen to search. If I do the same search criteria here, I get a couple of pages of random posts with many not having anything to do with the topic I was searching for to begin with. It is frustrating and time consuming and I agree with the poster, we need to find a better way of pinning these critical posts. It could save a Jag owner many thousands of dollars. I talked to a few different people about my transmission issues and almost everyone said that my transmission was toast. I even spoke to one shop that said they don't bother to test anything with the symptoms I described, they just go ahead and swap the transmission as it is less labor to do that than to troubleshoot other potential causes. Wow -
So I can say with complete confidence that this was indeed the issue I suffered from. The JLR software shows no more stored or pending codes to do with transmission and although I am always happier shifting with the J-Gate, the D position works fine and only has the slight flare through 3rd gear. As a reward to myself and the car for finally getting to the bottom of this, I went ahead and purchased all new brakes for the rear with vented, cross-drilled rotors, pads and even new parking brake components. Then its off to have an alignment done and after that I am just going to drive it for a while. It's been a bit of a journey getting the car to the point where it is and there is still more to do but nothing that parks it like the transmission issues did. Persistence pays off in the end
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and 1 others liked this post.
#9
07-02-2018, 11:29 AM
Veteran Member
Hi Bernie,
I can back-up your findings personally. Somewhere in here is "my" similar thread as well.
My first Tranny limp-home occurrence preceded having my Left Rear bearing start coming apart. At the time I didn't associate the two. Just a few months ago I had a slew of weird alerts pop up (all of which you listed) "and" a grinding brake disc on the Right Rear. Sure enough, the hub bearing was going out. I went with rebuilt hubs versus rebuilding them myself and I'm pretty glad I did. In both cases the bearings just fell out of the hub upon removal. When I removed the right rear, the ABS reluctor ring fell off the hub too! (No wonder I was getting ABS type alerts). It's quite possible that the hub casings themselves were damaged and that a mere rebuild would just invite the return of these problems very quickly.
What still amazes me from both your story (and others) and my own experiences is that there was never any indication that the rear bearings were starting to go south until they were almost completely on a "Florida beach." No whining or whuring whatsoever. How strange.
Congrats on your fix. And I agree - it's a fabulous drive without warnings / alerts, and a tranny that's shifting properly!
Enjoy.
I can back-up your findings personally. Somewhere in here is "my" similar thread as well.
My first Tranny limp-home occurrence preceded having my Left Rear bearing start coming apart. At the time I didn't associate the two. Just a few months ago I had a slew of weird alerts pop up (all of which you listed) "and" a grinding brake disc on the Right Rear. Sure enough, the hub bearing was going out. I went with rebuilt hubs versus rebuilding them myself and I'm pretty glad I did. In both cases the bearings just fell out of the hub upon removal. When I removed the right rear, the ABS reluctor ring fell off the hub too! (No wonder I was getting ABS type alerts). It's quite possible that the hub casings themselves were damaged and that a mere rebuild would just invite the return of these problems very quickly.
What still amazes me from both your story (and others) and my own experiences is that there was never any indication that the rear bearings were starting to go south until they were almost completely on a "Florida beach." No whining or whuring whatsoever. How strange.
Congrats on your fix. And I agree - it's a fabulous drive without warnings / alerts, and a tranny that's shifting properly!
Enjoy.
#10
07-07-2018, 08:40 PM
Senior Member
The ZF transmissions control modules (TCM), starting with the 5HP, use CAN bus to talk to the ABS. The TCM uses data from the ABS sensors to detect transmission faults. It looks like it never occurred to the clever and resourceful engineers that came up with that idea that ABS sensors and wheel bearings can fail too. Consequently, if your wheel bearing is shot, you can get all kinds of spurious transmission faults "detected" by the TCM. Make sure your ABS is perfect before you start messing with the transmission.
#12
07-25-2018, 03:02 PM
xk8 trans
#14
11-04-2018, 05:46 PM
Senior Member
Hey Cat Lovers,
I think I am in the right thread but wanted to run a couple of my issues past you guys. I have an 06 with XK8 Convertible with 122k miles. About a month ago I started hearing random rattling, usually after driving away from a fews days of being parked. It sounded like something dragging on the ground. It lasts for maybe 10secs, then goes away and when it does get DSC, Cruise and ABS messages. But the rattle goes away. Car drives great and after a restart messages go away. 10 days ago getting on the freeway and accelerating car seemed to just not respond to the pedal, you could hear the engine click like it was missing and then a slam into gear and boom the car was fine.
Yesterday wife and I are driving, the same thing starts to happen. We are doing 30 and I am accellerating mildy up an incline and I said to my wife hear it missing, The engine felt like it shut off for 3-4 seconds and then it slammed into gear (we are doing 40ish now) like a tranny drop from a stop to light up the tires. We got error messages for about 5 mins and then went away and the car drove perfectly for the 10 miles home. I got home and checked codes and had a C1235 Rear Right Wheel speed signal comparsion fault and a P1111/$11 Intake Temp Sensor Circuit Intermittent High Voltage. --- But there were no engine codes in the Scan or OBD readings.
Today we were on the freeway cruising around 60 when the error messages came up and they included Transmission Fault. The car was running but it wouldn't upshift from 3rd gear. We got off the freeway and pulled over. From a stop the car wasn't rolling like it should when I took my foot off the gas, and yet it didn't feel at all like the tranny was slipping. I think the Tranny was staying in 3rd. I shifted to R, N and D - And each time the Transmission slammed from position to position. I shut off the car and restarted it and still there. We drove a few blocks, we were actually going to take a look at getting a new Jag Convert. Before getting out of the car I plugged in the computer and got a P0720 Output Speed Sensor Circuit Malfunction and a Po701 Combination of impossible Substitute functions. When the comp read the codes the error messages shut off. A quick test of the tranny and it shifted normally.
We spend 20 mins looking at Ftypes (they didn't have any with a light colored interior) and then drove home. 8 miles on the freeway and I am barley accellerating up a slight incline at about 70 and the Yellow light starts flashing on the dash - Transmission Fault comes up for 1 sec and then goes away. The car has no power and seems like it's in Limp Home mode. And while trying to move over a couple of lanes to the right the lights go out and the car seems fine. I punch it and the car flies up to triple digits smooth as can be. Comes home without issues (only 5 more mile). Plug in the computer at home and get the same codes.
Does this sound like a a wheel bearing issue? The rattle noise when it's cold seems like something metallic dragging along, but then it goes away. The breaking on the car seems a little soft. But when the error messages are off the car is running beautifully.
Thanks for sharing your knowledge.
Dave B
I think I am in the right thread but wanted to run a couple of my issues past you guys. I have an 06 with XK8 Convertible with 122k miles. About a month ago I started hearing random rattling, usually after driving away from a fews days of being parked. It sounded like something dragging on the ground. It lasts for maybe 10secs, then goes away and when it does get DSC, Cruise and ABS messages. But the rattle goes away. Car drives great and after a restart messages go away. 10 days ago getting on the freeway and accelerating car seemed to just not respond to the pedal, you could hear the engine click like it was missing and then a slam into gear and boom the car was fine.
Yesterday wife and I are driving, the same thing starts to happen. We are doing 30 and I am accellerating mildy up an incline and I said to my wife hear it missing, The engine felt like it shut off for 3-4 seconds and then it slammed into gear (we are doing 40ish now) like a tranny drop from a stop to light up the tires. We got error messages for about 5 mins and then went away and the car drove perfectly for the 10 miles home. I got home and checked codes and had a C1235 Rear Right Wheel speed signal comparsion fault and a P1111/$11 Intake Temp Sensor Circuit Intermittent High Voltage. --- But there were no engine codes in the Scan or OBD readings.
Today we were on the freeway cruising around 60 when the error messages came up and they included Transmission Fault. The car was running but it wouldn't upshift from 3rd gear. We got off the freeway and pulled over. From a stop the car wasn't rolling like it should when I took my foot off the gas, and yet it didn't feel at all like the tranny was slipping. I think the Tranny was staying in 3rd. I shifted to R, N and D - And each time the Transmission slammed from position to position. I shut off the car and restarted it and still there. We drove a few blocks, we were actually going to take a look at getting a new Jag Convert. Before getting out of the car I plugged in the computer and got a P0720 Output Speed Sensor Circuit Malfunction and a Po701 Combination of impossible Substitute functions. When the comp read the codes the error messages shut off. A quick test of the tranny and it shifted normally.
We spend 20 mins looking at Ftypes (they didn't have any with a light colored interior) and then drove home. 8 miles on the freeway and I am barley accellerating up a slight incline at about 70 and the Yellow light starts flashing on the dash - Transmission Fault comes up for 1 sec and then goes away. The car has no power and seems like it's in Limp Home mode. And while trying to move over a couple of lanes to the right the lights go out and the car seems fine. I punch it and the car flies up to triple digits smooth as can be. Comes home without issues (only 5 more mile). Plug in the computer at home and get the same codes.
Does this sound like a a wheel bearing issue? The rattle noise when it's cold seems like something metallic dragging along, but then it goes away. The breaking on the car seems a little soft. But when the error messages are off the car is running beautifully.
Thanks for sharing your knowledge.
Dave B
The following users liked this post:
TrevLevin04XKR (09-06-2021)
#16
11-05-2018, 08:42 AM
Hey Cat Lovers,
I think I am in the right thread but wanted to run a couple of my issues past you guys. I have an 06 with XK8 Convertible with 122k miles. About a month ago I started hearing random rattling, usually after driving away from a fews days of being parked. It sounded like something dragging on the ground. It lasts for maybe 10secs, then goes away and when it does get DSC, Cruise and ABS messages. But the rattle goes away. Car drives great and after a restart messages go away. 10 days ago getting on the freeway and accelerating car seemed to just not respond to the pedal, you could hear the engine click like it was missing and then a slam into gear and boom the car was fine.
Yesterday wife and I are driving, the same thing starts to happen. We are doing 30 and I am accellerating mildy up an incline and I said to my wife hear it missing, The engine felt like it shut off for 3-4 seconds and then it slammed into gear (we are doing 40ish now) like a tranny drop from a stop to light up the tires. We got error messages for about 5 mins and then went away and the car drove perfectly for the 10 miles home. I got home and checked codes and had a C1235 Rear Right Wheel speed signal comparsion fault and a P1111/$11 Intake Temp Sensor Circuit Intermittent High Voltage. --- But there were no engine codes in the Scan or OBD readings.
Today we were on the freeway cruising around 60 when the error messages came up and they included Transmission Fault. The car was running but it wouldn't upshift from 3rd gear. We got off the freeway and pulled over. From a stop the car wasn't rolling like it should when I took my foot off the gas, and yet it didn't feel at all like the tranny was slipping. I think the Tranny was staying in 3rd. I shifted to R, N and D - And each time the Transmission slammed from position to position. I shut off the car and restarted it and still there. We drove a few blocks, we were actually going to take a look at getting a new Jag Convert. Before getting out of the car I plugged in the computer and got a P0720 Output Speed Sensor Circuit Malfunction and a Po701 Combination of impossible Substitute functions. When the comp read the codes the error messages shut off. A quick test of the tranny and it shifted normally.
We spend 20 mins looking at Ftypes (they didn't have any with a light colored interior) and then drove home. 8 miles on the freeway and I am barley accellerating up a slight incline at about 70 and the Yellow light starts flashing on the dash - Transmission Fault comes up for 1 sec and then goes away. The car has no power and seems like it's in Limp Home mode. And while trying to move over a couple of lanes to the right the lights go out and the car seems fine. I punch it and the car flies up to triple digits smooth as can be. Comes home without issues (only 5 more mile). Plug in the computer at home and get the same codes.
Does this sound like a a wheel bearing issue? The rattle noise when it's cold seems like something metallic dragging along, but then it goes away. The breaking on the car seems a little soft. But when the error messages are off the car is running beautifully.
Thanks for sharing your knowledge.
Dave B
I think I am in the right thread but wanted to run a couple of my issues past you guys. I have an 06 with XK8 Convertible with 122k miles. About a month ago I started hearing random rattling, usually after driving away from a fews days of being parked. It sounded like something dragging on the ground. It lasts for maybe 10secs, then goes away and when it does get DSC, Cruise and ABS messages. But the rattle goes away. Car drives great and after a restart messages go away. 10 days ago getting on the freeway and accelerating car seemed to just not respond to the pedal, you could hear the engine click like it was missing and then a slam into gear and boom the car was fine.
Yesterday wife and I are driving, the same thing starts to happen. We are doing 30 and I am accellerating mildy up an incline and I said to my wife hear it missing, The engine felt like it shut off for 3-4 seconds and then it slammed into gear (we are doing 40ish now) like a tranny drop from a stop to light up the tires. We got error messages for about 5 mins and then went away and the car drove perfectly for the 10 miles home. I got home and checked codes and had a C1235 Rear Right Wheel speed signal comparsion fault and a P1111/$11 Intake Temp Sensor Circuit Intermittent High Voltage. --- But there were no engine codes in the Scan or OBD readings.
Today we were on the freeway cruising around 60 when the error messages came up and they included Transmission Fault. The car was running but it wouldn't upshift from 3rd gear. We got off the freeway and pulled over. From a stop the car wasn't rolling like it should when I took my foot off the gas, and yet it didn't feel at all like the tranny was slipping. I think the Tranny was staying in 3rd. I shifted to R, N and D - And each time the Transmission slammed from position to position. I shut off the car and restarted it and still there. We drove a few blocks, we were actually going to take a look at getting a new Jag Convert. Before getting out of the car I plugged in the computer and got a P0720 Output Speed Sensor Circuit Malfunction and a Po701 Combination of impossible Substitute functions. When the comp read the codes the error messages shut off. A quick test of the tranny and it shifted normally.
We spend 20 mins looking at Ftypes (they didn't have any with a light colored interior) and then drove home. 8 miles on the freeway and I am barley accellerating up a slight incline at about 70 and the Yellow light starts flashing on the dash - Transmission Fault comes up for 1 sec and then goes away. The car has no power and seems like it's in Limp Home mode. And while trying to move over a couple of lanes to the right the lights go out and the car seems fine. I punch it and the car flies up to triple digits smooth as can be. Comes home without issues (only 5 more mile). Plug in the computer at home and get the same codes.
Does this sound like a a wheel bearing issue? The rattle noise when it's cold seems like something metallic dragging along, but then it goes away. The breaking on the car seems a little soft. But when the error messages are off the car is running beautifully.
Thanks for sharing your knowledge.
Dave B
wj
#17
11-05-2018, 10:17 AM
Great idea as i was wondering if that $65-70 puller at Harbor would work, pulling the rear, and front wheel bearings.
The front ones are frozen to their mounts, on the 07, luckily unlike the 04's, you could change 07's ball joints with out removing the bearings.
Have the feeling the rears will be impossible without the right puller, i would like to have one that will do both.
As sooner or later they will need done, with the best plan is to have things before hand.
According to my memory the front wheel bearings for the Vanden Plas, will take the regular XJ8 bearings, if you reuse the old wiring harness.
Does anyone know???
The front ones are frozen to their mounts, on the 07, luckily unlike the 04's, you could change 07's ball joints with out removing the bearings.
Have the feeling the rears will be impossible without the right puller, i would like to have one that will do both.
As sooner or later they will need done, with the best plan is to have things before hand.
According to my memory the front wheel bearings for the Vanden Plas, will take the regular XJ8 bearings, if you reuse the old wiring harness.
Does anyone know???
#18
11-05-2018, 04:43 PM
Hey Cat Lovers,
I think I am in the right thread but wanted to run a couple of my issues past you guys. I have an 06 with XK8 Convertible with 122k miles. About a month ago I started hearing random rattling, usually after driving away from a fews days of being parked. It sounded like something dragging on the ground. It lasts for maybe 10secs, then goes away and when it does get DSC, Cruise and ABS messages. But the rattle goes away. Car drives great and after a restart messages go away. 10 days ago getting on the freeway and accelerating car seemed to just not respond to the pedal, you could hear the engine click like it was missing and then a slam into gear and boom the car was fine.
Yesterday wife and I are driving, the same thing starts to happen. We are doing 30 and I am accellerating mildy up an incline and I said to my wife hear it missing, The engine felt like it shut off for 3-4 seconds and then it slammed into gear (we are doing 40ish now) like a tranny drop from a stop to light up the tires. We got error messages for about 5 mins and then went away and the car drove perfectly for the 10 miles home. I got home and checked codes and had a C1235 Rear Right Wheel speed signal comparsion fault and a P1111/$11 Intake Temp Sensor Circuit Intermittent High Voltage. --- But there were no engine codes in the Scan or OBD readings.
Today we were on the freeway cruising around 60 when the error messages came up and they included Transmission Fault. The car was running but it wouldn't upshift from 3rd gear. We got off the freeway and pulled over. From a stop the car wasn't rolling like it should when I took my foot off the gas, and yet it didn't feel at all like the tranny was slipping. I think the Tranny was staying in 3rd. I shifted to R, N and D - And each time the Transmission slammed from position to position. I shut off the car and restarted it and still there. We drove a few blocks, we were actually going to take a look at getting a new Jag Convert. Before getting out of the car I plugged in the computer and got a P0720 Output Speed Sensor Circuit Malfunction and a Po701 Combination of impossible Substitute functions. When the comp read the codes the error messages shut off. A quick test of the tranny and it shifted normally.
We spend 20 mins looking at Ftypes (they didn't have any with a light colored interior) and then drove home. 8 miles on the freeway and I am barley accellerating up a slight incline at about 70 and the Yellow light starts flashing on the dash - Transmission Fault comes up for 1 sec and then goes away. The car has no power and seems like it's in Limp Home mode. And while trying to move over a couple of lanes to the right the lights go out and the car seems fine. I punch it and the car flies up to triple digits smooth as can be. Comes home without issues (only 5 more mile). Plug in the computer at home and get the same codes.
Does this sound like a a wheel bearing issue? The rattle noise when it's cold seems like something metallic dragging along, but then it goes away. The breaking on the car seems a little soft. But when the error messages are off the car is running beautifully.
Thanks for sharing your knowledge.
Dave B
I think I am in the right thread but wanted to run a couple of my issues past you guys. I have an 06 with XK8 Convertible with 122k miles. About a month ago I started hearing random rattling, usually after driving away from a fews days of being parked. It sounded like something dragging on the ground. It lasts for maybe 10secs, then goes away and when it does get DSC, Cruise and ABS messages. But the rattle goes away. Car drives great and after a restart messages go away. 10 days ago getting on the freeway and accelerating car seemed to just not respond to the pedal, you could hear the engine click like it was missing and then a slam into gear and boom the car was fine.
Yesterday wife and I are driving, the same thing starts to happen. We are doing 30 and I am accellerating mildy up an incline and I said to my wife hear it missing, The engine felt like it shut off for 3-4 seconds and then it slammed into gear (we are doing 40ish now) like a tranny drop from a stop to light up the tires. We got error messages for about 5 mins and then went away and the car drove perfectly for the 10 miles home. I got home and checked codes and had a C1235 Rear Right Wheel speed signal comparsion fault and a P1111/$11 Intake Temp Sensor Circuit Intermittent High Voltage. --- But there were no engine codes in the Scan or OBD readings.
Today we were on the freeway cruising around 60 when the error messages came up and they included Transmission Fault. The car was running but it wouldn't upshift from 3rd gear. We got off the freeway and pulled over. From a stop the car wasn't rolling like it should when I took my foot off the gas, and yet it didn't feel at all like the tranny was slipping. I think the Tranny was staying in 3rd. I shifted to R, N and D - And each time the Transmission slammed from position to position. I shut off the car and restarted it and still there. We drove a few blocks, we were actually going to take a look at getting a new Jag Convert. Before getting out of the car I plugged in the computer and got a P0720 Output Speed Sensor Circuit Malfunction and a Po701 Combination of impossible Substitute functions. When the comp read the codes the error messages shut off. A quick test of the tranny and it shifted normally.
We spend 20 mins looking at Ftypes (they didn't have any with a light colored interior) and then drove home. 8 miles on the freeway and I am barley accellerating up a slight incline at about 70 and the Yellow light starts flashing on the dash - Transmission Fault comes up for 1 sec and then goes away. The car has no power and seems like it's in Limp Home mode. And while trying to move over a couple of lanes to the right the lights go out and the car seems fine. I punch it and the car flies up to triple digits smooth as can be. Comes home without issues (only 5 more mile). Plug in the computer at home and get the same codes.
Does this sound like a a wheel bearing issue? The rattle noise when it's cold seems like something metallic dragging along, but then it goes away. The breaking on the car seems a little soft. But when the error messages are off the car is running beautifully.
Thanks for sharing your knowledge.
Dave B
Simply jack up the car at each corner, one at a time and place your hand on the top and the bottom of the wheel.
Rock it back and forth and report how much movement you have in the wheel. If there is little to no movement, you probably have another issue but if it moves a noticeable amount, congratulations, you may have just saved yourself a ton of money and heartache.
Get back to us with what you discover and please do all four wheels, one at a time.
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Redline (11-06-2018)
#19
11-06-2018, 09:59 AM
Veteran Member
The following users liked this post:
Redline (11-06-2018)
#20
11-12-2018, 09:40 AM
Hey Cat Lovers,
I think I am in the right thread but wanted to run a couple of my issues past you guys. I have an 06 with XK8 Convertible with 122k miles. About a month ago I started hearing random rattling, usually after driving away from a fews days of being parked. It sounded like something dragging on the ground. It lasts for maybe 10secs, then goes away and when it does get DSC, Cruise and ABS messages. But the rattle goes away. Car drives great and after a restart messages go away. 10 days ago getting on the freeway and accelerating car seemed to just not respond to the pedal, you could hear the engine click like it was missing and then a slam into gear and boom the car was fine.
Yesterday wife and I are driving, the same thing starts to happen. We are doing 30 and I am accellerating mildy up an incline and I said to my wife hear it missing, The engine felt like it shut off for 3-4 seconds and then it slammed into gear (we are doing 40ish now) like a tranny drop from a stop to light up the tires. We got error messages for about 5 mins and then went away and the car drove perfectly for the 10 miles home. I got home and checked codes and had a C1235 Rear Right Wheel speed signal comparsion fault and a P1111/$11 Intake Temp Sensor Circuit Intermittent High Voltage. --- But there were no engine codes in the Scan or OBD readings.
Today we were on the freeway cruising around 60 when the error messages came up and they included Transmission Fault. The car was running but it wouldn't upshift from 3rd gear. We got off the freeway and pulled over. From a stop the car wasn't rolling like it should when I took my foot off the gas, and yet it didn't feel at all like the tranny was slipping. I think the Tranny was staying in 3rd. I shifted to R, N and D - And each time the Transmission slammed from position to position. I shut off the car and restarted it and still there. We drove a few blocks, we were actually going to take a look at getting a new Jag Convert. Before getting out of the car I plugged in the computer and got a P0720 Output Speed Sensor Circuit Malfunction and a Po701 Combination of impossible Substitute functions. When the comp read the codes the error messages shut off. A quick test of the tranny and it shifted normally.
We spend 20 mins looking at Ftypes (they didn't have any with a light colored interior) and then drove home. 8 miles on the freeway and I am barley accellerating up a slight incline at about 70 and the Yellow light starts flashing on the dash - Transmission Fault comes up for 1 sec and then goes away. The car has no power and seems like it's in Limp Home mode. And while trying to move over a couple of lanes to the right the lights go out and the car seems fine. I punch it and the car flies up to triple digits smooth as can be. Comes home without issues (only 5 more mile). Plug in the computer at home and get the same codes.
Does this sound like a a wheel bearing issue? The rattle noise when it's cold seems like something metallic dragging along, but then it goes away. The breaking on the car seems a little soft. But when the error messages are off the car is running beautifully.
Thanks for sharing your knowledge.
Dave B
I think I am in the right thread but wanted to run a couple of my issues past you guys. I have an 06 with XK8 Convertible with 122k miles. About a month ago I started hearing random rattling, usually after driving away from a fews days of being parked. It sounded like something dragging on the ground. It lasts for maybe 10secs, then goes away and when it does get DSC, Cruise and ABS messages. But the rattle goes away. Car drives great and after a restart messages go away. 10 days ago getting on the freeway and accelerating car seemed to just not respond to the pedal, you could hear the engine click like it was missing and then a slam into gear and boom the car was fine.
Yesterday wife and I are driving, the same thing starts to happen. We are doing 30 and I am accellerating mildy up an incline and I said to my wife hear it missing, The engine felt like it shut off for 3-4 seconds and then it slammed into gear (we are doing 40ish now) like a tranny drop from a stop to light up the tires. We got error messages for about 5 mins and then went away and the car drove perfectly for the 10 miles home. I got home and checked codes and had a C1235 Rear Right Wheel speed signal comparsion fault and a P1111/$11 Intake Temp Sensor Circuit Intermittent High Voltage. --- But there were no engine codes in the Scan or OBD readings.
Today we were on the freeway cruising around 60 when the error messages came up and they included Transmission Fault. The car was running but it wouldn't upshift from 3rd gear. We got off the freeway and pulled over. From a stop the car wasn't rolling like it should when I took my foot off the gas, and yet it didn't feel at all like the tranny was slipping. I think the Tranny was staying in 3rd. I shifted to R, N and D - And each time the Transmission slammed from position to position. I shut off the car and restarted it and still there. We drove a few blocks, we were actually going to take a look at getting a new Jag Convert. Before getting out of the car I plugged in the computer and got a P0720 Output Speed Sensor Circuit Malfunction and a Po701 Combination of impossible Substitute functions. When the comp read the codes the error messages shut off. A quick test of the tranny and it shifted normally.
We spend 20 mins looking at Ftypes (they didn't have any with a light colored interior) and then drove home. 8 miles on the freeway and I am barley accellerating up a slight incline at about 70 and the Yellow light starts flashing on the dash - Transmission Fault comes up for 1 sec and then goes away. The car has no power and seems like it's in Limp Home mode. And while trying to move over a couple of lanes to the right the lights go out and the car seems fine. I punch it and the car flies up to triple digits smooth as can be. Comes home without issues (only 5 more mile). Plug in the computer at home and get the same codes.
Does this sound like a a wheel bearing issue? The rattle noise when it's cold seems like something metallic dragging along, but then it goes away. The breaking on the car seems a little soft. But when the error messages are off the car is running beautifully.
Thanks for sharing your knowledge.
Dave B
Wondering if you have checked your wheel bearings and what have you discovered?