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Q: High Idle, stalls when a/c or defrost is turned on and dies completely after some rough idling. If turned back off car is fine.

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Changed IAC. Looked at grounds. Cleaned the flap inside the air flow unit. Cleaned and check mass air flow sensor. New air filter. Doesn't seem to have any vacuum leaks. When started it stay around 2000rpms longer than it should. Jumpy when at idle around 8-9 hundred rpms. Sometimes sticks around 3k rpms when gas is pressed in idle. When driving car idles high and no gas is needed it will literally drive at that high idle without the gas being pressed. (As if cruise control is on but its not). When accelerated hard it will stick up in the 2-3k range of rpms and we have to shift to neutral and tap gas to get it to come back down.

My car has 76000 miles.
My car has an automatic transmission.

Hi there. The fact you able to get the idle speed to drop by tapping the gas pedal, lead me to believe the high idle is due to a sticking accelerator cable. Another possibility could be, a faulty throttle body not allowing the throttle to return to the closed position. Proper diagnoses should be performed to avoid unnecessary repairs. I recommend having your vehicles high idle be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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