High Idle Problem
My truck has a high idle problem. I cleaned the IAC valve, Seafoamed the engine twice, but still no luck. It also has a bad case of pinging. Even with Premium gas in it. It takes a min. for the idle to go down at stoplights and when shifting. Idk what else to check. I checked the EGR valve, and the truck had a new upper intake gasket installed a year ago....Any feedback would be much appreciated!!! BTW, it's a '97 4.0 5 speed.