1991 PF - Rough Idle and stall only sometimes

[Captain_Crazy]

My 91 runs good 95% of the time, BUT at times, it surges at a stop and the tac jumps up and down a little and stalling at times at idle, But then it goes away for a while. then come back?? I just cleaned the PVC Valve, was a little blockage. but still have the problem. My son seen a youtuber saying it was his Idle air control Valve under the intake on the one he was working on. ???

Edited August 8, 2017 by Captain_Crazy

[Mrelcocko]

My 91 runs good 95% of the time, BUT at times, it surges at a stop and the tac jumps up and down a little and stalling at times at idle, But then it goes away for a while. then come back?? I just cleaned the PVC Valve, was a little blockage. but still have the problem. My son seen a youtuber saying it was his Idle air control Valve under the intake on the one he was working on. ???

I would start with a tune up. Plugs,wires,rotor,cap etc...

 

Sent from my SM-G530T using Tapatalk

[Captain_Crazy]

I did all that like 5000 miles ago. Maybe the fuel filter?

 

Edited August 9, 2017 by Captain_Crazy

[adamzan]

Sounds like the common MAF plug wiring issue. Try wiggling the connector and see if it makes a difference. Clean all the contacts as well. What happens is the wires get loose at the connector end due to people not unhooking it to change the air filter.

 

Fuel filter would not cause this, though it couldn't hurt to change it anyway.

[RF600]

Run another ground for the Maf. I ran mine to the core support where another ground was to insure the ground would be good. I would also check the iac valve.