1989 Corvette engine Varying idle RPM

[Stephen L.]

Help!!! Have a problem with varying idle RPM after engine warm up. Have already replaced the TPS (Throttle position sensor) and the IAC (Idle air control) with no good results. Any ideas? Questions?

Suggestions appreciated

Steve

[Jimmy G.]

Re: 1989 Corvette engine Varying idle RPM

There are two relays on the firewall that I had go bad causing the same issue. One was Mass Air Flow Burn Off sensor. Cant remember the second one. Both just above the battery as I recall.

[Joe L.]

Re: 1989 Corvette engine Varying idle RPM

There are two relays on the firewall that I had go bad causing the same issue. One was Mass Air Flow Burn Off sensor. Cant remember the second one. Both just above the battery as I recall.

Jimmy and Stephen-------


Both relays are related to the mass airflow system and both are the same------GM #14089936. They are still available and not very expensive. By the way, the same part number relay was also used for the fuel pump relay application.

[Stephen L.]