88 4.3L caprice RPM problem

[kevn83]

Hey guys,

I just get my Caprice back on the road after it has sat for a few months. I had to replace the head gasket last Dec due to a cracked radiator... and the car has just sat since. I wanted to get it back on the road so I was checking it out again etc... she starts and drives pretty good except that I have a really high idle... I did not have that before. It even affects the car when trying to stop. If I start off at a complete stop the car will reach at least 25 mph without me even touching the gas pedal.

do any of you have any idea what could be wrong? should I try to fill up the gas tank? there is some old gas in there I don't know if that would cause this sort of problem or not. The only other thing I can think of is that the air cleaner might not be making a tight seal with the TBI... how does the air cleaner seal to the metal cylinder that sits on the TBI?


Thanks for any advice.

[bhw33191]

You know, my car has "or had" the same idling problem. You'd step on the gas to make it go down and it would, but then it would slowly creep up again. I have no clue what the problem was, but i think its gone now.

[silicon212]

Look for something on the throttle body called the "Idle Air Control". This takes the place of the idle circuit on a carb. Its job is to moderate airflow into the TB when the throttle is closed, allowing enough air for the engine to idle. These can go bad for any number of reasons, and one such symptom of a failed IAC solenoid is the fast idle.