Hello, for some reason, when my ac is on and I am in drive (idling), sometimes the rpm gauge starts to bounce from 400-700 rpm. It sounds like it is stuttering. Once it even stalled as I was reversing without even pressing the gas pedal. When I put it into neutral at a stop light, the issue seemed to go away. I am sure that hitting the 400rpm mark signifies some issues. Also the ac compressor kept turning on and off when this happened. Any advice and suggestions would be greatly appreciated. Thank you.
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1998 White Toyota 4Runner Limited V6 4WD - 255k miles
My former service advisor at the dealership suggested that it could be the compressor. I did put R134a refrigerant in the system during early summer so I think it’s filled up. Also serpentine drive belts were changed around 3 or 4 years ago. I will look into the vacuum suggestion. Thanks guys
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1998 White Toyota 4Runner Limited V6 4WD - 255k miles
I’d clean your IAC the AC cycling on and off is normal unless your Fan was at max speed with outside air selected instead of recirc and it’s above 85.
You can clean it without removing the throttle body by removing the vacuum line that goes to the intake and spraying throttle body cleaner in the port and watch for black stuff coming out the air inlet hole in the throat of your throttle body.