Rough idle

Asked by 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

10

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

210

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.

10

Yup. It chugs a chugen

10

Does it cost alot to fix

210

New cap and rotor?

210

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.

10

I bought the car off rightway. 5 months ago still maken payments

210

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

210

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

10

Ok i will do i just checked it and added a qt of oil

10

What cap and where is it located

95,105

Better do a compression check you could have a dead or very weak cylinder.

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