Hey everyone,

So I think that awful throttle body hose that snakes under the intake manifold is leaking on my 2006 STR (90k miles). I say “I think” because it’s impossible to actually get back there to check it without taking the intake off. Symptoms are: low coolant light comes on every 400 miles, smells of antifreeze, a minimal amount of coolant residue on the undercarriage in the transmission area and coolant streaks running down the bell housing. I cannot find evidence of a coolant leak in any other place and there is no evidence of coolant in the oil. So...I'm preparing to change that hose but there are numerous parts that will be need to be changed in the process. Here is a list that I'm working on:


Throttle body coolant hose: AJ89554
EGR Valve, bolts, and gaskets: AJ88582, AJ88559, AJ88560, AJ82190
Thermostat and gasket: AJ811788, AJ83445
Water outlet seal: C2C11477010
Intake-Supercharger connector plate x2: AJ86892
Supercharger outlet duct gasket: NCC7735BA
Upper intake manifold gasket x2: AJ88047
Lower intake manifold gasket: AJ85392

Questions that I have for the forum members that have changed this hose:
Am I missing any other parts?
Is it common for the EGR valve to fail? (I thought I’d change it since I’ll have access to it but it’s expensive!!)
Is it really necessary to change the supercharger connector plates? (I read on another forum post that these were changed during the process of changing the same coolant hose).

Thanks in advance!
John

 

you can come back to the egr easily as its one of the first parts to remove and last to refit . mine has never given me any trouble . but my freand xkr 4.2 egr did give trouble . and i just cleaned it out with brake clean and carby cleaner and refitted it , about a year ago with no further issues . id give that one a miss . other wise you are missing the horse shoe pipe that goes from the T/B to the EGR and id also be changing the pipe that returns the coolant from the EGR to the thermostat bypass housing along side the charge cooler. oh and of course some antifreeze . also there are two knock sensors under there as well and if you don't want to go under there for a while then id be doing those too.
otherwise thats a complete list.

 

Hi Datsports,


Thank you for the info! So adding those two hoses and the knock sensors, it looks like its going to be just over $1,000.00 in parts to change that hose plus the misc items...

 

i wouldn't bother replacing the Intake-Supercharger connector plate x2: AJ86892 or the
Supercharger outlet duct gasket: NCC7735BA as these are real easy to come back to as well if they are problematic . a light coating of locktight 515 will reseal them fine . or better still 3bond . as well as the S/C inlet elbow gasket (not listed ) if you separate it .
also i nearly forgot you really should replace the brake booster vac pipe o-ring in the S/C inlet elbow as well as the evap and pcv o-rings on the other side of the S/C inlet elbow wile your in there for a few dollars well spent . this is the time to do it !

 

Once the supercharger is out, the rear supercharger hold down boss (that reaches out under the elbow) can be slotted for ease of installation. Allows the elbow to be bolted to the supercharger before sliding the supercharger in (the two lower elbow bolts are tough to get to). Start the rear hold down bolt first and then slide the supercharger/elbow elbow assembly in.

Some back and forth about it in this thread:
https://www.jaguarforums.com/forum/s...ocation-97024/

 

Thanks everyone for the comments/advice. I decided to take the car to Jaguar to have them do a pressure test on the coolant system. The technician said the leak is coming from the thermostat housing where it connects to the engine block. Quote for replacing the housing: $1,767.00 I guess I'll be doing it myself.... Since I'm going to be in there, I decided to replace a few other common problems items that fail including the famous throttle body coolant hose that runs under the supercharger.
Thanks again!

 

Wow that price is extravagant ! It takes about two hours , to drain the coolant , remove and refit the coolant tank , piping , thermostat bypass manifold , and bleed the coolant sistum . There is just two o-rings sealing it , is your thermostat housing plastic or alloy , I wonder if there price includes up grading a plastic one to alloy ? If it's plastic it realy needs to be changed as well !

 

I feel your pain part of my upper radiator hose disintegrated into dust upon contact. It seems everything needs replacing the older it gets. I'm doing my thing too, it's fun knowing these jags and frustrating .

 

In addition to proactive replacement of mentioned parts consider also replacing the o-rings on the fuel injectors. Mine leak some air causing lean condition.

 

Well.. I'm now exactly a month into this project. I started the disassembly last Saturday. Everything went really smooth until I got to that S.O.B. EGR valve. What a royal pain in the ***. The bolts connecting it to the intake elbow seemed like they were fused to the EGR valve. Could not get a straight angle on them and keep the socket straight at the same time to avoid rounding them off (good thing I bought new ones). Unbolted the top of the EGR valve in frustration to try and get more room and even considered taking a saws-all to it to get to the bolts! In any case, I finally got it off and I'm glad I decided to spring for a new one because mine was corroded. Next pain in the *** issue was the bolts holding the EGR tube to the exhaust manifold. The rear one was stuck on so tight that it unscrewed the stud from the manifold. At first I thought it had broke off which sent me into a panic at the thought of buying a new manifold ($750) so I gave up for the day and didn't even bother to investigate this further. This Saturday I went at it again after a week long recovery and it turns out that half way up the stud, two of the threads were damaged preventing the nut from unscrewing completely; I hope Jaguar sells just the stud. Finally got everything off and it turns out that the heater hose connecting the EGR to the thermostat bypass pipe was leaking and when I grabbed ahold of it an tried to lift it out...it came apart at the joint where there was clear evidence of leakage. So in total, I've replaced the two hoses underneath the supercharger, knock sensors, thermostat housing inlet pipe (that the Jag tech said was leaking but showed no evidence of leakage) and the accompanying hose as well as 5 other misc. heather hoses that were is various stages of failure. Also waiting on the brake booster vac pipe o-ring replacement kit as suggested by Datsports. Any advice on getting the old brass fitting out?
Now.... I never, ever, ever want to do this again so, I need to get the supercharger rebuilt. I've read all the posts I could find about where to send it. PSE seems like a good option although some people complain of the turnaround time. Eurotoys claims 3-5 days once PSE receives it but others say that in reality it takes 2-3 weeks. I hope that this is not the case. Other options that PSE offers is porting and pulley upgrades. Some guys in the forum have mentioned that porting is a worthless option. Wondering if anyone has any comments on this.
Thanks!

 

couple of things .good work with the perseverance . it sounds like it payed off .
as for getting the brass fitting out , there are 4 bolts on the back of the blower that hold the s/c intake elbow on . if you remove those bolts the elbow just pulls off the rubber gasket . and then you have access to punch the fitting out from the inside !
i actually found it easier to refit the blower then refit the intake elbow back on the blower afterwards , i also took mine apart this way seemed more logical . and it saves the need to slot the rear bolt hole and fumble the spanner under the elbow for what would seem like eternity . the stud can be purchased at parts stores or any good engineering firm , or bolt & bearing supply merchant . does not need to be jaguar specific . just size,thread & tensile specific. i have to recommend doing the 1.5psi/6% pulley upgrade . stay away from the 3psi/10% its over kill. porting money will be better spent on celebratory beers for when the job is complete !! also check the EGR flex pipe carefully for cracks in the ribs. carry on your going great

 

Many threads on this and I have posted several very detailed instructions that deal exactly with your problems on the EGR as well as detailed parts list.

Have you looked??

https://www.jaguarforums.com/forum/s...-p0174-149418/

https://www.jaguarforums.com/forum/s...-hoses-102914/

Please read the links in these threads as many people have added to the procedure over the years.
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Thanks clubairth1,

I did research the forum before proceeding and wouldn't have started this project without the advice/experiences of other forum members. I ordered the brake booster replacement kit as well as the elbow, connector, and tubing just to be safe. It appears to have previously leaked as it was slathered with some kind of grey silicone.

Wondering if anyone knows about the hose that connects the two fuel rails... I tried to order a new one and Jaguar told me that part wasn't serviced and that I would have to buy the entire fuel rail assembly for only $765. Just to replace a simple rubberish hose.. sighs. I wanted to replace it because it disappears once the supercharger is in place.

 

I havnt seen any fail , and I'm sure it will do big miles compared to the injector o-rings , a second hand one on eBay is around $180 with injectors . I don't think you need to invest that kind of cash on the rail , Unless it looks damaged/perished .

 

Hi, I'm new to this forum. I live near Frankfurt, Germany. Bought my S type R new in 2007, now has 180,000 km on the clock, just went through the TÜV for the third time. I love it dearly.
The car is at the moment in the workshop of the Jaguar dealer in Frankfurt after a sudden loss of coolant. They worked on it all day on Friday, and are stuck completely, don't know what to do. They have narrowed the problem down to the two dreaded coolant hoses. They have received new hoses, but are unable to disassemble the old ones. I went there Friday evening, and talked to their chief mechanic, He showed me the hoses - the top end is free, but the other end goes under the blower, and they cannot access it, even though they have removed the cover of the blower. What should I tell them??
I would really appreciate help on this one, because I can see it getting expensive at a rapid rate of knots. Thanks in advance. Pete

 

They need to remove the thermostat manifold and egr and supercharger to repair it , it is going to be expensive . As it's no 5 minut job, The expensive part will be the hours ! Hense the need to DIY on these ageing Jaguars !
It does not sound that this jag agent is very on to it , as these guys will have access to itstuctions on this diognosis and repair , I hope your shore it's in the right hands .

As a new member you are required to post an introduction in the new members section .

 

Thanks for your help, Datsports. I'm not equipped for DIY, so I'm in the hands of the Jaguar dealers. I've tried all of them in this area, and this one (Glinicke) has been the best so far. If it's expensive, I'll just have to bite the bullet. I'm not clear on what EGR is, could you please clarify.

I'll post my intro as a new member as soon as I can figure out how to do it.

 

BTW. There a many threads in the S type forum with step by step how to's for this procedure and also some short cuts or work arounds ( cutting the SC mounting locator at the back for easy slip on install).
Also many extensive parts listings and things to change while that deep in the motor.

Try searching

 

I listed several links above and those also contain very good links. It will take some reading to figure it all out but none of this is new or unusual.
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Here is a link from the stickys at the top of the s type forum section , happy reading :

https://www.jaguarforums.com/forum/s...-repair-38911/