I recently did a tune up on a 94 for a lady who claims she has done nothing to the car for 5 years, not even an oil change. All i did was a basic tune-up (i.e. plugs, wires, oil/air/fuel filter change) and if you have done this on this car, you probably would know that it nearly impossible to get to the passenger side plugs without removing the alternator. So i did so. After completing the tuneup, I started the car and the idle started at 2k and rose from there to about 4k. I decided to take it for a drive down the road and wi\hile coming to a stop, when the tranny kicks down to 1st, the motor idles at 2k and i have to plant my foot on the brake to keep it from going anywhere. At that point a check engine light came on. i took it a friend witha scanner the next day and it read a code indicating the IAC was faulty. so i replaced it but nothing changed. the lady wants her car back but i dont know what to do! Some have told me to replace the TPS but i dont want to just throw parts at it in hopes it fixes it. Any help or direction is greatly appreciated. Thanks!

 

u put all the plug wires on the right way?

 

Check all the vacuum lines and electrical plugs.Thats where I would start.

 

Sounds like vacuum leak to me. Is the brake booster line plugged in?

Edit: also check the wiring to the IAC. Had the plug on the wire side go bad before.

 

Wrong forum..... the 3.4L engine is covered on the "V6 Tech" engine forum. I'll move it there for you.

 

If you replaced the IAC valve and it's still throwing the code then there is something wrong with the connector or wiring from the sensor to the PCM. Any chance a wire got pulled or something while you had the alternator out and changing out the plug wires?