Mechanics

ENGINE SOUNDS UP AND DOWN

2004 Chevrolet Malibu • 4 cylinder FWD Automatic • 67,000 miles

Engine sounds up and down : when I turn it on the engine doesnt sound like one tune, the sound is up and down and even when I drive or stop at stop sign I can the sound is waxing and waning
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Shadim77
January 11, 2011.



If the idle is going up and down, check for vacuum leaks and check the idle air control valve (IAC). It is located on the throttle body and is responsible for maintaining a steady idle.