I have a 1994 gmc Sierra sle k1500 and it's idling fast and I can't find out what is causing it
Do you have an engine light on? if so get it scanned
My advise is to replace the Air idle mixture valve. Easy fix. my 95 GMC had the same trouble after I replaced the intake gasket. It is cheap to replace $50.00 Simply unplug the wiring harness and un screw the old one, and replace it. Hope this was helpful
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