95 GMC Jimmy High Idle P0507
Then with a fuel trim total of 7 you don't have a major problem there. Since your trims are positive the ECM is adding fuel so there is a possibility of a minor vacuum leak. If the trims get closer to zero at 2500 that helps to confirm. You can also pinch off all of the vacuum hose branches while watching trims at idle and see if they go closer to zero.
George
George
Yea I'm leaning more and more towards a vacuum leak. I'm baffled I can't find it. I smoked the intake through the brake booster hose and didn't really find anything. I also blocked off the brake booster hose and the second port in at the back of the intake manifold with it running and no change to the idle. I going to hunting with propane tomorrow and see if I can find something. This thing is driving me nuts.
Then make sure to check fuel trims at idle and 2500 for more clues. I also would not ignore the guidance in that IAC article you reference, it has some good ideas. It states that an IAC count of 0 is out of bounds.
George
George
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