[NoDOHC]

First of all, this is an s4 engine, right? The s5s have a full range TPS.

I ought to look around, I have a stock TPS somewhere that is slightly scalded (engine fire due to PD leak) but worked fine on my '86 until I installed the Haltech, at which point I removed it. (If I can find it, you can have it).

I tested the voltage between each of the pins and ground. (With the connector plugged in).

I found that one of them was 0 Volts (sensor ground) one was 5 Volts (Sensor supply) and one was variable from 0.6V to about 4V based on the position of the plunger. Setting the TPS such that this one ran around 0.6-0.9 Volts at idle made for optimal operation.

I am not sure that the sensor is your problem. The dealer would have nothing to gain by finding your sensor to be ok. (They won't sell you a part). I am guessing that it is ok and your meter is lying to you.

I really wish that I could remember exactly what the values were for the TPS, but it has probably been 3 years since I adjusted an s4 TPS.

If I were looking at it, I would go by the factory manual. Check timing then TPS, then idle adjustment with the test jumper installed the timing again. If you can't notice a change when you adjust the TPS throughout the entire range, chances are that something else is wrong.

If all other ideas fail, you may check your CAS pickup gap and your idle mixture adjustment screw (which is hopefully capped).

It is late now, hopefully tomorrow I can dig that sensor up for you.