Idle Problems... Engine Surges & BLM's @ 150 - Third Generation F-Body Message Boards

JerseyMark · 07-19-2006, 09:42 AM

Hey everyone,
Im having issues with my 91 RS 305TBI. The car isnt running right at idle. The car surges & sometimes dies. I hooked a computer to it and found that the BLM's are almost always at 150 during idle. Im wondering if this has something to do with it? Im about to go get a new IAC valve, but I thought I would throw this up here to see if I could get any feedback before I wasted any money.

Thanks,
Mark Balistreri

fast L98 · 07-19-2006, 08:52 PM

My 91RS is doing the same thing. Anybody have any suggestions as where to start troubleshooting? My mechanic set the timing and ran it on the computer and found nothing.

JerseyMark · 07-20-2006, 07:18 AM

I have two possible solutions.

1) IAC valve is bad. (Cheap & Easy)
2) A cylinder misfire would cause lots of extra oxygen to go through the exhaust system. The O2 sensor would pick up this oxygen, tricking the computer into believing that the engine was running lean. Thus, adding all of the extra fuel. The extra fuel could make the car not idle right.