930 Intermittent fast idle
 

I took about a 2 hour ride sat morning to the Pittsburgh Vintage Grand Prix. Air temp in the high 60's low 70's.

Toward the end of the ride - I noticed a high idle when the car was in neutral. Otherwise it seemed to run fine

Normally idles at about 800 - 900 RPM. It was idling at about 2000 RPM.

Let the car sit all day - started it to go home and it idled and ran fine.

Any suggestions? Is this anything to worry about? I have never noticed it doing this before.

Thanks,

Could be related to the AAV - Aux. Air Valve that allows more air to enter the engine as the car warms up, resulting in a fast idle. It is supposed to close gradually, based on engine temp, but it could be stuck open or intermittant I suppose. Something to check.

I bet it is your decel valve.