When I turn on my AC, the idle goes too low that it causes a nasty vibration at times. Not low enough to make the car die, but just enough to cause the vibration. The car does have pretty high mileage (142,000 km), but other than this vibration issue, my boy is just about perfect. I have not done any modifications to the engine, changed the battery, or added any audio items. Plain ol' standard 2004 Camry.

I searched and searched and narrowed it down to 2 things
1. Throttle body cleaning
2. IAC

I have done no.1 at the shop, slightly better...but not much.No.2 I have no clue about. Can someone shed some light on this part, and my issue in general?

Thanks in advance.

 

I think the AC is the problem, it won't react well to make the vibration and that makes it idle.

 

You mean the compressor needs some servicing?

 

The 2.4L is a completely drive-by-wire system. There is NO IAC valve. The idle speed is kept constant by keeping the throttle plate slightly open. They cleaning the throttle bore and plate and see if this helps.

JJ

 

If it was the throttle bore/body...wouldn't it rattle even if the AC is off? The vibration is only when the AC is on.

 

The motorized throttle plate is used to maintain idle speed. When the AC is turned on, the throttle opening should be increased by the PCM to compensate for the load of the AC system. There are no adjustments that can be made to this throttle motor. The best that can be done is to try cleaning around the bore and plate, then disconnect your battery to erase any learned idle values. Then fire up the engine and let it idle for several minutes so it can relearn base idle.

JJ

 

Thanks Joel...I will try that!