when I put the truck in park the idle speed jumps up to about 1500 rpm and then settles down to about 750. I also notice that when driving and coming to a stop the engine will remain at high idle for a few seconds before coming back to normal. It seems to be more pronounced when the A/C is on. This is killing my mileage. I've gone from around 15 mpg to 14 mpg since the problem started. I was going to start by cleaning the throttle body but I wanted to get your thoughts before doing anything. Thanks.
Oct 22, 2008 at 7:40 AM