1999 Questions for all other cars rpm down while switch on t

1999 ALL OTHER MAKES ALL OTHER MODELS
74,000 MILES • 4 CYL • 4WD • AUTOMATIC
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ASHWANI VERMA
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  • 1 POST
When I switch on AC of my car, its rpm come down from 1000 to 500 or less, I have shown it to machanic who could not rectify its default.
Mar 9, 2009 at 12:54 AM
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MIKE H R
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with out the ac on the engine idles about 1000 rpms and when you turn the ac on the engine goes down to about 500. This is a normal thing. when the ac is off there is no drag on the engine so it runs a little faster. when you turn the ac on the compressor turns on using the engines power to turn the compressor. This is more common in 4 cylinder engines. You can see this while you drive the car and turn the ac on the car looses a little power. especially noticable when passing someone and the compressor turns on.
Mar 10, 2009 at 10:22 AM