High idle 94 S4

[techspy]

I am having a high idle. Here are the details;

- It only starts after driving awhile.

- When it first starts, I can blip the throttle and it goes back down but after a few more minutes, blipping the throttle wont make it go back down and sometimes makes it raise a bit.

I recorded Freescan and found the following;

- Initially it shows a TPS of 0 and I can blip the throttle and it goes back down.

- After blipping doesn't help, I can see that the TPS is sometimes showing 1 instead of 0.

- When I got home it was still doing it so I checked and found that the throttle cable was not taught and had enough slack and was not holding the throttle open.

- I pushed on the butterfly lever that the throttle cable is connected to, trying to push it toward the closed position but it didn't change the high idle and the TPS stayed at 1.

- I turned the car off for about 5 seconds and started it again and the idle was perfect and showed a TPS of 0.

- I recently disconnected the battery for a day to reset the ECM tables but it is acting the same was as before.

- I also reset the IACV but it did the same thing on the next drive.

- I have checked for leaks several times and found none but being that it rights itself after restarting the engine, I am not thinking that is the issue anyway.

- EBPV and throttle jack have been removed (blocked off the vacuum lines) and have adjusted the IAC readings using Freescan with the bleed valve and have the IAC settling down to 25-30 after warming up.

I am leaning towards replacing the TPS and IACV. The Lotus parts are about $300 but the ones listed below came from a cross reference list but I would like confirmation before ordering.

Anyone have any suggestions? Anyone know if these parts are the correct cross reference parts and will work?

http://www.autozone.com/autozone/parts/_/N-9gsmgZ1...

http://www.autozone.com/autozone/parts/Idle-Air-Co...

Thanks!

[Le TVR]

TPS data shows 0 or 1 when closed?
IIRC the normal was something like 25 closed to 200 full open?

Regarding the IAC setting the programmed value will only be held until you switch the car off. It is reset on restart.

[BibsTLF]

Both parts are about £60, close to $90 I guess.

Get the IACV out and give it a good clean. What's the IACV value trace look like from a cold start?

[V8 FOU]

Pull the cable from the IAC and see what happens. It should revert to base idle. Go for a drive with it disconnected, and if all is well replace the IAC.