Rough idle

Asked by Connie Mar 27, 2016 at 10:35 PM about the 1991 GMC Sierra 1500 C1500 SLE Extended Cab LB

Question type: Maintenance & Repair

Rough idle won't stay running have change
elec.spark control, idle air control,plugs,map
sensor,tps, and the ecm.. Still running rough but if
you unscrew the IAC it idles high but the miss
smooths out...I am at a loss any ideas

12 Answers
80

Wendy answered 8 years ago

My car is a 2005 chevy aveo it. Stalls out when take off oil light blinks off and on what could the problom

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940

Hec4570 answered 8 years ago

Almost sounds like it's missing. Have you changed the spark plug wires? I would pulling by one answer if you notice a difference. Could have a bad wire. Sounds like a timing issue.

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940

Hec4570 answered 8 years ago

Pull your cap if you not changed it. Check inside it. See if you see white lines on the inside. Best describes and white lightning marks. Could be bad cap that's causing a misfire.

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940

Hec4570 answered 8 years ago

Sorry I was answering the questions. Above for this forum. But have you checked to make sure you have oil?

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940

Hec4570 answered 8 years ago

My rule of thumb is always check fluids and change oil when buying a used Alvarez that is not certified.

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Skylargial answered 6 years ago

Pull throttle body, easy to do, clean w/ carb and choke cleaner using a nylon brush only. Makes a hell of a difference.

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Your Answer:

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