Any expert advice would be MUCH APPRECIATED

After trunk was stuck open on wife a week ago, the car went into limp mode almost immediately ("DSC unavailable, Parking Brake fault, and engine fault") after I secured trunk lid and tried to drive it home for her. The engine light cleared twice after 15 min, then 30 min wait times but came back within 100 feet of running with limp mode again. OBDII fault code clearing (only P2135 code found) did NOT help for long. Had to have it towed because it kept going into limp mode before getting out of the parking lot.

I replaced trunk latch twice, as first one was defective, and then a new Bosch 900 CCA battery per JagV8's suggestion. New battery reads 12.7V at rest, 14.1V running. No codes found other than P1000.

Yesterday, I went thru exterior car wash then test drove for 20 miles on a freeway at 70+ mph. Engine ran flawlessly. Outside temp 82 deg F and clear skies. Visited old college on return at (10-15 mph thru parking lot) and car went into limp mode once again. Waited 20 min to see if fault would clear (like it used to) and went into limp mode twice more. OBDII fault code clearing not helpful this time either. Couldn't get out of parking lot and had to get towed home AGAIN!

I've had this recurring problem with the P2135 fault and limp mode but luckily always at low speeds (under 35 mph) and it always cleared after letting it sit for 15-20 min. Finally decided to look at TPS to see if it could be faulty with erratic resistance thru rotation as I viewed in generic TPS troubleshooting YouTube video. Can't find any resistance dropouts and the inside of the TPS looks absolutely new - see pics. I'm using a digital multimeter so that's not ideal.

Should I just spray it out with elec contact cleaner, waterproof plug, reinstall with black gasket RTV and cross my fingers or should I throw a new TPS at it??? Anything else I should try?

This is a non-SC engine so TB/TPS is in the front of the intake under engine cover. I have never seen any water in that area after car washes as I understand moisture could be the culprit for these problems.

HELP!

 

You need a new TPS.

 

I'm going to try the knock-off Denso 1985003300 route first as Jag dealer still won't sell TPS separately.

I was surprised (as was the parts guy) that a new Throttle Body assembly (w/ TPS) is currently "only" $412 plus $10 for gasket.

 

P2135 is definitely TPS related, it happened on my XJR and I swapped in a replacement (although used) throttle body and it's never been back... see here https://www.jaguarforums.com/forum/x...8/p2135-78429/

Just be aware if you remove the throttle body to get access to the TPS you need to replace the gasket as they are a one-shot only piece.

And you need a 5-point Torx bit to remove the screws that hold the TPS to the throttle body.

 

MOVED TO NEW POST.

I just received and installed a new TPS unit to try and cure a recurring P2135 engine fault and limp mode nightmare (recently posted).

When TPS first installed, engine starts right up but idles and runs erratically. I revved it to 2k rpm and it just settles and shuts off. No fault codes were stored or pending. Tried this 3X, same result.

Well, I just found some other posts about TPS rotational adjustments to set idle voltage across TP1. I've surmised that this may be different for different MY and engines so does anyone have the correct setting for my 05 Base S-Type 4.2L? Is a setting of 0.75V close enough?

After resetting to correct idle voltage as described above, do I need to perform a hard reset (battery disconnect) before I'm done? I did just replace the battery before installing the TPS.

Could this be why dealer only sells TPS installed on entire TB assy?