OK, my write up on the limp mode fix from moisture on TPS, well documented and this is for 2003 STR.which is NOT the same as at least the 2005 as I discovered.

Not a big diff but whatever..I am also assuming that anyone can remove the intake baffles etc considering its 2 clamps and an air connection so my starting point is the plenum removal. You should read through BEFORE doing as there is a critical step regarding clamps that MUST be purchased beforehand( i lived and learned)
ALSO.. you MUST have at least 2, if not 3 cans of CRC TB cleaner, one can of CRC lectric parts cleaner, and also 1 can of CRC dialectric grease(CRC is the best period) Since the MAF is exposed, might as well get CRC MAF cleaner to.

Step 1"; remove the 10MM bolt directly under the front of the plenum. your best friend here is a ratcheting 10 mm wrench. Note that the bolt holds down the slip connector and it is attached to the wire loom so once the bolt is removed, just wiggle the slip connector around to release from plenum.. no need to try and remove froom the cable

tps001.jpg?t=1299118109

Step 2: with a long tool, undo the TOP CLAMP ONLY from the plenum. I used a 1/4 drive with a very long xtension and a 9/32 socket. Then pry away the rubber from the aluminium all around..if you just get it started you can do the rest with your fingers. You need to break the seal of the rubber and aluminium. move the plenum up and to the right to remove, then remove the lower part of the rubber.
tps002.jpg?t=1299118503

STEP 3: Remove 2 electrical connections, one left, one right, both need a small flathead to compress the lock mechanism..its easy. BTW the one on the left is the bain of our existence the TPS. Clean those connectors now with lectric cleaner and shoot in some dialectric to the female ends now( i love saying that, sounds dirty)
tps004.jpg?t=1299118703
tps003.jpg?t=1299118727
next step: Remove the 4 bolts holding the Throttle boddy. These are 8 MM and are very simple to remove by just doing the initial break of the bolt and the rest is by hand DONT DROP..front right bolt in the pic below
tps005.jpg?t=1299118856

Next step:
Lift off throttle body...there is a thin gasket underneath so take care to grab and clean it up. Also, you will now see the 2 coolant connections on the left side..see below for gasket and connections
tps007.jpg?t=1299118991
tps006.jpg?t=1299119019

Ok next part. First off, take a big rag/towel and plug up the intake hole the throttle body came off..no need for fluid in there.
You need to remove those 2 clamps. This is easy as they pry right off with a flat head. HOWEVER..these clamps are NOT REUSABLE. Crazy design but it is what it is so have on hand basic screw down clamps. Push the end of the hose with a bigger flat head and the hoses will pop off, also dumping a small amount of fluid..(hence the rag!)

pic of throttle body removed
tps008.jpg?t=1299119484
go ahead and spray crc tb cleaner all into the intake and wipe it down..its a mess for sure after 8 yrs

ok so here is the removed TB..it is black on the underside and its thick. Followed by the cleaned TB..not a trick thats the real difference, I had to soak in gas and TB cleaner and scrape with a plastic spine tool
tps009.jpg?t=1299119881
tps011.jpg?t=1299119935
Ok so now to remove the TPS sensor and clean and seal. Like the other guide, i id not have a 5 star bit, and the wrench idea was not easy but it worked. I would highly suggest against removing the 2 5 star bolts with a wrench, and getting the proper bit. This part of the project took the longest so lesson learned. It was ridiculous to do this without the simple bit but oh well. pic below of TPS
tps010.jpg?t=1299120234

Ok TPS removed and you can see the crusty flaky stuff on the center...THAT is the process of moisture.. use the lectric cleaner and spray the hellout of it and use the straw that comes with the cleaner to gently agitate it to remove. Then spray the other side of the TB completely getting Under the black housing thoroughly.
tps012.jpg?t=1299120411

next, using sensor safe permatex as shown below, run a bead all around the TPS.. put back on TB and tighten down, wipe away excess and let sit for an hour.
tps013.jpg?t=1299120456

congrats.. yo have now solved the STR limp mode issue.. AND you will probably have much better throttel response ESPECIALLY if you added the mafioso intake in the same day like i did !!

im not showing reinstall as this should be self explanatory..

let me know if there is anyting you need for clarification or if I missed something!!

Regards

Paul AKA Fergs03r

 

Well done!!!

 

Just one question are you going to do the plug change yourself? IF so can you take pics of your step by step process I noticed one thing missing from your list in the signature area, Mina Lower Mesh Grill

 

Paul, you're write-up is amazing! Thank you. If ya all are interested, ya can not hook coolant lines to throttle body (by-pass it). You won't have to worry about coolant line under supercharger as this is a return line from throttle body. otherwise a totally awesome detailed tutorial on throttle body TPS clean-up.

 

Great point BFs, but how exactly could we by pass it?

 

Nice write up. Great pics.

 

What a great write! Mods - this should be included in the FAQ's.

I was really surprised by how dirty the TB was. Is that common to be that black?

Also, I've been reading a bit on porting the TB. But what I don't know is if there would be any benefit to doing it on my NA 4.2L V8. I've seen where that "lip" just above the butterfly valve in the TB is eliminated and the valve plate done as well. I just don't know if it's worth the effort. Any comments?

Rob

 

yes plugs will be done, documented with pics next week..along with a mina exhaust instal, and later a full pic install of a mina pulley
i love the pic docs to help out the forum..let me know what else you want..i basically am obsessd so I do everything.

oh.. how bout a full rear and front brake job....coming soon..!!!!

anyone want that??

Maybe ill go down as the best how to pic submitter (ill pull my inner charlie sheen!!) what a whaack job....

 

I did it

Although I did mine at the ends of the hoses. Left the tb lines intact and looped them together

 

yes with an 8 yr old under relatively normal conditions this is norm for muck.. do not bother with the port..just clean it... as good as a port vs a dirty TB ... removing the lip will cause back air leakage , think vacuum so whats the point.
porting the TB NEEDs to be coupled with a slot of other intake and exhaust mods to see any thing.....waste of tiime

 

Hey thanks again for all the excellent work you've done in such a short amount of time. Have you thought of making videos on youtube as tutorials and posting them here rather than pics?

 

Wow, what a fantastic write up.....excellent job and thanks so much for sharing!

I'm sure one of the mods will be along shortly and this post will be made FAQ

 

jag79, to by pass coolant lines to TB all ya do is connect the in and out coolant lines together via a 3/8 coupler. This information was provided to me and performed by Mafioso. As far as any ill effects- I believe the coolant lines go tto the TB as a means for a quick way to warm-up the TB in winter conditions. Mine will have this performed when the 3 lb pulley, intake elbow, and plugs go in in a week or so (almost unlocked from ice/snow).

 

Thanks amigo for the info, I think I'm going to pull the trigger also and go for the pulley upgrade(still debating to go either with the 3lbs or 1.5lbs with a low temp thermostat);if I do that then I might as well get Mafi's air intake also

 

Nice job. Thanks for taking the time and effort to write and post this....

 

@fergs03R - thanks for the advice on the TB. Looks like I have another Jag project this spring, cleaning my TB! Me wife will be soooo happy! lol.

 

Thanks for this useful write up , FAQed

 

But why is moisture getting into your TPS sensor?



There was a service action (S159) on early Stype-R to apply a "sealing patch" (round piece of black duct tape)


Issue:A concern has been identified on 2003-04 MY S-TYPE R vehicles within the above VIN range. It is possible that during washing of the vehicle, by car wash or jet wash, the water can run through the cowl panel grille-fixing hole into the throttle position sensor housing. This can result in the throttle position sensor failing to function, the engine management system defaults to ‘limp home’ mode, and a warning MIL is displayed.
A sealing patch is available to prevent water flowing directly from the cowl panel grille onto the throttle position sensor.

Action:
On 2003-04 MY S-TYPE R vehicles within the above VIN range, install a sealing patch on the mounting hole located on the suspension turret cross brace at the bracket securing it to the bulkhead.


The mounting hole is what the wiper cowl is screwed down into.

What i have found is that even from the factory they would install this patch then run the screw for the wiper cowl right thru the patch defeating the whole purpose if putting it on.

When i come across the TPS code and water ingress in the connector, i replaced the T-body, reseal this patch and do not put the screw back in for this hole, and i seal the back of the TPS connector with silicone sealer. Making sure to cover all the pins/wires and the open slots adjacent to the pins see pic where the slots are.

I have not had any problems after with the cars after resealing this way.



great post on fixing the TP sensor.

 

Alldatadiy said not to clean the TB:

CAUTION: Do not attempt to clean the throttle body. The bore and the throttle plate has a special coating applied during manufacture which should not be removed.

 

This quote above is debatable.

I along with many "older" members here have had the same advise. We had elected to clean the TB and have had no problems, a search will discover that it is ok to clean the TB.