P0509 OBD II Trouble Code Idle Air Control Circuit High

How to diagnose, repair, and info on causes of a P0509 engine code which pertains to a high reading in the idle air control circuit. Also includes links to relevant forum topics on the code.

Symptoms of P0509 OBD II Trouble Code

Common Causes of P0509 OBD II Trouble Code

Severity of P0509 OBD II Trouble Code

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