phils89sc
Registered User
My 89 SC has been doing something very weird for the past few days. It starts and idles fine. After it warms up, say I am at a stop light with the car in gear and the a/c on, maybe also when it is off, the idle will drop a little too low, and then, it seems like the engine will cut out or there will be an instant loss in idle speed to make it appear that the engine is going to stall, then it catches and goes back to normal idle. This can happen two or three times per minute. I have no problems off idle and no issues with driveability or power.
Another weird thing it does, when you start it cold, like in the morning, it does not do the normal high idle and slow drop down to normal idle. What it does do is start up, idle goes to just over a grand, then suddenly drops down to normal idle speed. If you start it after warming up, I will then get the normal momentary high idle, but then as it is dropping down to normal, it will do till about 1100-1200 rpm, then 'fall', like it is cutting out to a normal idle. All the other SC's I have had, when you start the engine cold, it goes high idle, then slowly drops back to normal idle.
Could this be a problem with the IAC?
Another weird thing it does, when you start it cold, like in the morning, it does not do the normal high idle and slow drop down to normal idle. What it does do is start up, idle goes to just over a grand, then suddenly drops down to normal idle speed. If you start it after warming up, I will then get the normal momentary high idle, but then as it is dropping down to normal, it will do till about 1100-1200 rpm, then 'fall', like it is cutting out to a normal idle. All the other SC's I have had, when you start the engine cold, it goes high idle, then slowly drops back to normal idle.
Could this be a problem with the IAC?