Question about 2004 GMC Envoy

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RUNS ROUGH WHEN AIR TURNED ON, LOOSE RPM'S

When I turn the ac on, if the engine is at idol, it will actually drop my RPM's so low that it kills my engine. It is somewhat affected by turning the heat on but majorly affected by the AC blower. I can only use my AC if I am driving more than about 15 mph so the RPM's stay high.
Also, I have an issue with the instrument panel occasionally. Without any known cause, I will occasionally turn my car on to find the gauges flickering and completely unresponsive. I will drive for a few miles while they flicker at the zero position and they will beep as if I just turned my key to the ignition position and they will all return to the proper positions.
Any ideas? When I turn the ac on, if the engine is at idol, it will actually drop my RPM's so low that it kills my engine. It is somewhat affected by turning the heat on but majorly affected by the AC blower. I can only use my AC if I am driving more than about 15 mph so the RPM's stay high.
Also, I have an issue with the instrument panel occasionally. Without any known cause, I will occasionally turn my car on to find the gauges flickering and completely unresponsive. I will drive for a few miles while they flicker at the zero position and they will beep as if I just turned my key to the ignition position and they will all return to the proper positions.
Any ideas?

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The A/C compressor clutch may be bad

Posted on Dec 08, 2008

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