Alright everyone, I finally got my hands on a 2004 XJR with 89k miles. I can’t say enough about how well kept the car is. I drove from Orlando to Virginia and the car didn’t skip a beat.

On another note, the last 15 miles of the drive I went to pass someone doing 50 in a 55 (I’m from California, this is unacceptable). When I gunned it to pass I got a thud when it shifted, tire screech (I think the traction control light flashed) then it reved like it wasn’t in gear, then it dropped in to gear and went. I thought maybe it was just traction control cutting me off.
Next day, while accelerating mildly from a roll, I got the same thing, plus transmission fault/ restricted performance note. I pulled obd codes with a cheap reader and only had P1111.

After sitting an hour or two I started it up and no fault or restricted performance. Drove it a short while and it seemed fine. The issue seems to be at lower steady speed then accelerating.

Trans fluid was changed recently. It doesn’t have any other symptoms other than a kazoo sound when it shifts (heard it maybe twice) at lower speeds. It goes through gears manually fine. My initial thought is to check fluid level, then maybe valve bodies and seal replace. I’ve also read about wheel speed sensors causing problems. I’m going to keep searching and reading but any thoughts would be appreciated!

Has anyone done the trans adaptation reset themselves? I’m in the country so specialists aren’t close.

I’m going to keep reading and searching, a Jag specific diagnostic setup is something I want. Any links to where to buy it is also appreciated.

 

As a 2004, it seems to be suffering what I suffered with a 2003. I found that a reflash of the TCM cured the problem. Of course here we are 16 years later, so memory at dealers and shops may have faded about this simple fix. Early cars did suffer problems like this. The 2003 was 7 years old when I took it over, and when I changed to a 2007 in 2016, I had no problems with the later car, so mods had clearly been done somewhere either by Jaguar or ZF.

 

I think a misfire can do this.
When I had my tranny problems, the Forums and mechanics all said, fix misfires first.
New plugs and coils? Oil around the spark plugs from leaking cover?
Good luck,
Rob

 

Brad,

I have extensive experience (almost 2 years) with this exact problem on a supercharged car and I'm sorry to say I have not found a solution. If my car is driven normally it shifts very smoothly and gives me no problems. If I ask for passing power between 50 and 70 it will sometimes miss the downshift to 3rd and either blow into neutral or grab a gear very suddenly and chirp the tires. Rarely, I also get all kind of dramatic hooting and popping in and out of gears. Sometimes it will go into a Gearbox Fault with Restricted Performance, and sometimes it will just continue as if nothing happened. To quickly clear the faults you have to pull over and re-start the car TWICE. If you search on my posts in this Forum you will find a description of all the work I have done to my car to resolve this, and the various (unhelpful) error codes I have recorded. I believe I have done EVERY single thing that has ever been suggested as a solution including plugs and coils, (my car never sets misfire codes and runs perfectly), TCM S/W update, trans fluid and pan and seals and connector sleeve replace, full valve body rebuild and TCM test (at Eriksson in CT), replacement of all ABS sensors etc. I'm probably forgetting a few things but I have made no progress in solving this. On my car it happens rarely enough that I have enjoyed many miles of pleasurable driving, but I can never make a passing move without planning an escape if it fails. My next attempt to solve the problem is to dismantle the entire intake system to look for a pinhole and after that I have a used TCM that I will swap in for my final attempt at a resolution before I pull the transmission for a full rebuild.

If you or anyone else on here can figure this out and help me get my car to behave, I will send you a case of your favorite liquor or anything else you prefer of similar value. My car is in beautiful shape for it's age and everything works perfectly except for this shifting problem.

Best regards (and Luck)
Jeff

P.S: None of the ZF experts I have consulted think this is a mechanical issue with the gearbox itself but who knows.

 

JCalhoun

Thank you for that reply. I was thinking I would do all you did but may look elsewhere first.

Did you ever look at trans temps or possible plugging of the trans cooler? I’m wondering if there is a back up there and build up of pressure is causing problems.

 

Brad,

I replaced my trans cooler lines and have also used my diagnostic tool to monitor trans temp. Totally normal. If anything, my car is less likely to misbehave when it is fully warm. I have flushed the fluid with ZF Lifeguard 6 twice and checked the level using the correct procedure (which is a pain in the ***) 3 times. If your trans oil has never been replaced you should do that service including the seals, pan and connector sleeve but I think it unlikely that this is your problem unless there is an obvious leak and the fluid is low. I say this because your symptoms are so precisely similar to mine and not similar to people who have had low fluid levels.

Jeff

 

Before performing any diagnostic or repair work, use a voltmeter to determine the voltage across the battery terminals with the ignition in the OFF position. It should be a minimum of 12.6 volts. If not, charge the battery for five hours at 2 to 5 amps and retest.

Many of the electrical and mysterious 'gremlins' chased across these forums are the result of a failing or weak battery, so eliminate that as a possibility first.

 

Thanks Jeff. I’ll keep you posted. Glad I’m not the only one with this issue. I just talked to my dad (he used to work on aircraft in the Navy) until I was blue in the face about possibilities. At least I feel better about driving the damn thing.

 

thanks I’m all over it!

 

Lots of info here:
https://www.jaguarforums.com/forum/x...ooting-191572/

Also, just a thought and it doesn't really sound like the problem but do you by chance have adaptive cruise control? I had in on my 05 SV8 and it would do strange things when I Ould pass other drivers from time to time.

Also important, have you been able to replicate the problem?

 

I do have adaptive cruise. The problem is very repeatable. Slow roll then gas it. If I gas it from a stop no problem. If I spin tires a little from a stop then let of the gas then get back on it, it starts slamming gears and chirping tires.

I did go out today with a cheapie code reader, replicated the problem. After a few restarts and clearing the fault I down shifted to 2nd from about 55 through the gears and gunned it a little and got code P1643

 

https://www.google.com/search?rlz=1C...cdRAnEQ4dUDCA0

 

BradK,

Having purchased a similar excellent condition 2005 XJ8L NA in February 2020, I will say your experience, minus the P1643 code, match my road trip experience this past week. I drove from Colorado to Utah and back and yes, exact same symptoms. Although these transmissions are - if I am correct, different variations of the same ZF between your XJR and my XJ8L, the common area is the TCM program that tells the transmission when and how to shift based upon throttle position and other variables like speed and kickdown and shift points. Mine has had transmission work by the DPM prior to sale and the update campaign in 2008.

With a cheapo OBDII code reader you are not going to get into the innards of the module functions. They are good for quick reading the codes, but not pinpoint testing for failed components like you can do with IDS, or SDD and see what is going on between the TCM and transmission sensors.

For that you need a professional Jaguar Diagnostic setup like IDS/SDD, or the other aftermarket units that will perform all functions including module commissioning. You can get bootleg software and a suitable dedicated PC - I set up a Panasonic Toughbook running one of the Virtual setups, but the fully compatible Vehicle Communication Module is the main cost.
I managed to locate an OEM Ford/JLR Rotunda VCM with cables from another forum member so between IDS and SDD I can do most of the things a dealer can, and I found out at my local JLR service shop that they even use the forums like this one for tips of diagnosing the older vehicles, so that says a lot for the expertise here.

Having gone across three model years and four versions of the XJ and with my experience working at several auto manufacturers for manufacturing and testing systems, I can say some of its programs have not changed in several model iterations or even manufacturers using the same ZF.

One example is the Evaporative emissions systems in all four of my Jaguars have the symptom of fill the tank, get a restricted performance message right after accelerating onto the road, and then resets when the throttle is off and the car coasts for 10-15 seconds with no code saved by the time I get a reader in place. One of those even had two weeks in the dealer to completely chase the Evaporative system issue and every associated Service Notice, and they eventually believed me it was a failing ECM, not the evaporative codes triggering the Restricted Performance. New ECM and problem vanished.
I suspect the same for the TCM program where the basics between Sport mode and normal drive mode are canned programs with only small variations on the overall function to compensate for different performance of the power plant to the manufacturer specification.

So just to really understand what is happening with the TCM, you should get setup with a IDS/SDD diagnostics or something equivalent if you plan on keeping your XJR for any length of time.

 

First, I'm in awe of your 80mph message on that drive. Second, if I recall there's a good shop in Harrisonburg, MotorWerks, and it might be worth a conversation with them. In the DC area, there is a great transmission place (County Transmission in Vienna), and a very good indy shop that does only Jags (Top Line Jaguar Diagnostics in Springfield just south of the Beltway adjacent to 95). I've had experience with the last two. I meant to take my new-to-me x308 to MotorWerks for a prepurchase checkout in Harrisonburg, but Imisread an internet listing and ended up at a shop south of Staunton. That was a 100-mile test drive!

Finally, if you see a grey '04 XK8 running around your area, I almost bought that one but balked at the wind/road noise. The car was otherwise visually and mechanically pristine. The owner ultimately decided to keep the car. But he told me he'd had it serviced at MotorWerks and was very happy with them.

Cheers, from Annandale, VA

 

Eliotb,

Thank you for the tip on motorwerks! I did think there would be anyone in Harrisonburg that would look at it, let alone someone I may trust. My wife’s uncle is a BMW guy, I’m asking him if he’s used them.

I’ll look out for that XK. Are there any Jag groups in Va or cars and coffee groups?

The 80 MPH avg speed didn’t last long once I got further up 81.

 

Regarding clubs: I belong to the Shenandoah Valley British Car Club based in Waynesboro which has monthly events and an annual car show, first weekend in October. Home ... There are several folks from Harrisonburg in it, including a woman who's a doctor at one of your local medical groups who, with her husband, have taken over a beautiful old Rolls (late '20s I think). Very Nice folks. There is the National Capitol Area Jaguar Owners' Club, which I keep meaning to join, which has an annual concours event and usually one of the Jag dealers opens their shop one day a year for people to come put their cars up on lifts and tips from Jag Techs.

The place where ended up having my prepurchase checkout was just south of Staunton at Raphine up on a hill between 81 and 11 called Foreign Affairs. Mostly BMW and MB but otherwise nice folks. Also , In Waynesboro there is a very well known all-British shop run by a guy named Mike Gassman, Gassman Automotive. He is used by many of the folks in the SVBCC.

If anything else comes to mind I'll pass it along. And if you are interested in talking with the fellow in H'Burg who has the '04 XK8 that I almost bought, I will send along his email. He's in his '80s and also has an XF. He is a former Jag concours judge.

Eliot

 

Brad: Just a short followup. There was a “cars and coffee” over in Charlottesville that I get messages about via the SVBCC, but I think it’s sort of suspended at the moment. SVBCC costs like $20 or $25 for the year and the newsletter is good. I also traded notes with the XK8 owner in H’Burg, Chauncey (Chan) Dayton at this address: Mitchdayton@cs.com ... He’s happy to chat with you and offer far more local guidance than I can. He lives off 33 towards Elkton in a new development off to the right eastbound that has a bunch of duplexes. He just ditched his F and a Mini Cooper and replaced it with a 2021 cooper. He retains the XK8.

If you have to have access to the Jag diagnostic software for the car, I think your closest dealer is over in C’Ville. I’ve heard good things about the one in Roanoke. I’ve been treated well at Rosenthal in our area, but you might like that Top Line shop I mentioned as well.

Eliot

 

Thanks Eliot!

Chan lives very close to me I believe, I’ll send him a message. I have an appointment with motor werks on Monday to get the car scanned. The service manager said if he can’t get the info/codes no charge. So I like that already.

I did check fluid today, and cleaned the mechatronic connector just because. No change. I’ll check coils as well just in case.

 

Thanks Eliot!

Chan lives very close to me I believe, I’ll send him a message. I have an appointment with motor werks on Monday to get the car scanned. The service manager said if he can’t get the info/codes no charge. So I like that already.

I did check fluid today, and cleaned the mechatronic connector just because. No change. I’ll check coils as well just in case.

 

Alright everyone, I had the local shop scan for codes. They are below. The one that seems most interesting is the pressure transducer in the abs module...What bugs me is if I lock it in 3rd and accelerate, I still get restricted performance and trans fault even there is no shifting happening.