Ive had some very ruff and rich idle problems and did the TPS adjustment and all was within spec. But while I was at it and had the upper intake off I did some vaccum hose clean up. Anyhoo got it all back together and cranked the car and it revved and ran fine, idled good and great vaccum. Well while I was back under the hood I noticed the TPS plug was unplugged. I cleared the ECU and plugged it back in and now the car has very bad lopping idle and back fires and breaks up when revving. Any reason why it would run much worse with it plugged in? Did a bunch of searching and nothing really helped...any ideas.

 

maybe because it needs to be adjusted? search for a thread from damian in the advanced tech section about adjusting the TPS. or check the FSM.

 

whats the FSM???

sorry

 

That was what I went by (Damian thread and the FSM).
Just did a little checking on the range of the TPS and the green wire (second from the top) is smooth in voltage on the way up to full throddle but on the way back down to closed throddle it stays maxed out till about 1/4 throddle. Is this normal? The black wire (on bottom) works like it should. What throws me off is that the TPS dead on at closed throddle and still idles badly. I can understand that if it is off with the throddle open that would make it run poorly. But it has a very bad idle and vaccum.

 

C'mon Mike it's the Factory Service Manual, remember I sent you a link to the online PDF version to check your CAS?

 

Well I would check all vacumn lines to make sure that they are all good, and make sure you replace all the stock paper gaskets with the newer metal ones. Check the gaskets between Block/ Lim, LIM/ UIM, UIM/ TB.

 

All vaccum lines and gaskets are good. Intake has no leaks. I guess my question is...why does the car run better with the TPS unplugged and are the voltage readings on the green wire an indication of a bad TPS.