Question about 1991 Pontiac Firebird

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Searches for idle in closed loop

The car runs great until it enters closed loop then it idles rough and searches around 500-900 rpms. If you try to drive the car it won'ty accelerate and runs like complete garbage. We've changed plugs wires distributor and checked for any vacuum leaks and we have come up emtpy. any ideas?

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This could be many things. I had somewhat of a similar problem. Here are a few possiblilites though i wouldn't know unless i knew more. Before i do that though. If you press on gas while in neutral will the rpm drop WAY down and then possibly stall out?

Fuel Injectors might be going bad(least likely but possible)
Erg Valve
Oxygen sensor
Cpu
Your idle valve might be off
Timing might be off because of above.

Like i said i don't know exactally and i'm not THAT great and only someone who looks at it and stuff would know but i had somewhat similar problems. If you'd like to explain more email me darkspawnling@hotmail.com. Just add in your car and firebird or something in the subject. Hope it helps.

Posted on Feb 26, 2009

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Posted on Jan 02, 2017

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