Could someone point me to the FAQ (if there is one) for this ng ? Or , if someone has experience with a too-fast (like 45 mph sometimes !) idle on a 3.1 V6 , I'd be interested in your cure, if you found one . The motor has done this occasionally since around 70k miles . Now has 220k on the car (96 Corsica ), 50k+ since complete rebuild due to overheat/dropped intake seals . It's getting a bit worse now , and sometimes will drop to a normal idle (and sometimes won't) if I turn the key off and then back on quickly . I can't find any vacuum leaks , fuel leaks , and the car runs great otherwise , mileage around 30 MPG avg . It does not seem to be tied to the A/C idle step-up .