Bad AAC valve? posted by jkcizbck on September 12, 2008 at 04:29 AM
Message
screw to about 650 RPM. If it won't go that low, could be either a bad Air Regulator or vacuum leak would be the most common items to first look at. Remember, this has to be done when the engine is up to operating temperature as the air regulator is open when it's cold increasing the idle speed.