QuestionQUESTION: hi, i've got an 89 chevy caprice and when you let off the throttle you can really hear the ac system whining and vibrating. when you're on the throttle, it rarely does it. compressor is new, but wondering if it could be faulty or possible orifice tube plugged? belt drive is 100% perfect.
ANSWER: Hi,
You would have to put gauges on it to see if the orifice tube is plugged. A high high side adn low low side would indicate this but I have never seen a compressor make noise on decel only. What I have seen is improper belt installation, worn tensioner or incorrect belt length cause this problem on 5.0l and 4.3l engines. Does it make the noise if you unplug the compressor?
Wayne
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QUESTION: no, it definitely makes noise only when the compressor is engaging. it vfery well could be making some accel noise but I've got headers and pipes on this car, so it may go unnoticed lol. but definitely irritating on decel and stops having that vibration.
AnswerHI,
I have actually asked some colleagues about this problem you are having and one mentioned something similar happened to him on a Chevrolet truck when he installed a remanufactured compressor. He beat his head against the ground until giving in and installing another which corrected the problem.
Sorry I couldn't be more helpful. It would be great to hear this noise myself to help you diagnose it.
