I have a stumper here. 1992 Buick Park Ave Base with few repairs done to the engine. Replaced Cam Magnet and sensor 1 year back, Changed coil pack and module from Magotvox to ACDelco 6 months ago, replaced alternator after meltdown 3 months ago, and the infamous front engine mount over a year ago when I got the car. Bypassed VATS and installed remote start.

Yesterday car was driving fine, parked to go into store and when I return, Tried to start car and will not start until I give it a little on the accelerator. I have checked fuel pressure at pre-start (~40 PSI) running with Vacuum (~35 PSI) and no vacuum (~78 PSI). Have had the SES light come on before then went away withing a mile, pulled DTC and got the TPS code along with my favorite PRNDL code. (still trying to find tool to help with realigning the PRNDL.) Once car is started it will either stall or if keep on the accelerator for a bit, it will idle below 800 RPM. Any points of direction on this???

The first thought that jumped in to my head was the IAC being plugged up, stuck, or otherwise inoperative. Were you able to get the TPS code to go away, or is that still to be addressed?

Haven't cleared the codes out yet in the system. Just been watching to see if the SES light comes on again while driving. I was thinking about the IAC also but have seen here in other places about the prevalent FPR. I have been considering crossing off the FPR due to the numbers I have seen.

So I just got back from O'Reilly after installing the IAC. What a wonderful place to hide the top screw. Special screwdriver needed there. That fixed the problem. When I got the old one out, it was fully extended and stuck I would presume. First one I got at O'Reilly was a part number 2IAC23 MPI line. This one has what is known by GM as a dual slope valve. What I pulled out was a Triple slope. I went back in after seeing this and got the right one which is a Part Number 21813 BWD. This one is a triple slope. Just a word of advice for those who are looking at replacing the IAC that you should know which IAC your going to need. It is all determined by the VIN that will tell you what type you have. I knew about this due to having AllData here on my computer. The other interesting thing I had happen this morning while it was about 40 Degrees F was that I had a no start condition. Pulled two plug wires on one pack and had no spark jump. Went through the diagnosis process listed here in the forums on DIAG of ICM and found that I had a bad ground. Wire tap and wire to Negative on battery fixed that. Thank you rjolly87 for the pointer.

Here are some pics of the IAC that I pulled

Pintle itself that is very dirty. Sprayed port with carb cleaner and got more out of that.




As you can see here the pintle is fully extended. It took a little bit of force to pull the unit out. While it is out put new in and keep old as a spare.