I'm doing the TPS and th IAC procedure, did the IAC allready and doing the TPS with a OTC, with the key on its at .38 and WOT at 4.30 volts. Can't get the votage at above .40 volts. Bad TPS? On my Turbo Buicks the TPS is slotted so the adjustment is very easy on the Camaro is seems it can't be adjusted. The only way to increase the TPS voltage I drilled out the mounting hole to get an increase in voltage but then the idle gets increased.

 

the idle will increase because you are telling the computer the throttle is opening. so it adds fuel and the IAC opens some. di you loosen both screrws? just asking. it should move.

 

Yes I removed both screws on the TPS but can't get more than .40 volts.

 

You don't need to adjust the TPS on 90-92 TPI cars. The ECM relearns 0 everytime it starts up. And over 4V at WOT is 100% so nothing is wrong there either.
The turbo buick ECM is an earlier, dumber design.

 

Thanks for the info. I got this off here.....https://www.thirdgen.org/newdesign/tech/tpimod2.shtml should had been more specific for the years I broke the TPS trying to adjust it. Is the IAC reset procedure correct to my car?

 

i guess that was part of speed density change.. i noticed the difference from my 88 formula 350 to my 91 formula 350..

 

So there is no TPS adjustment on my 92 Z28? But do a low .38 won't give any idle problems? Is there a ECM power disconnect under the hood to reset the ECM or I have to just disconnect the battery?