Code P0507 indicates the engine control module has detected an idle speed that exceeds the calibrated target by a significant margin. This typically points to an unmetered air entry or a malfunction in the idle air control system that allows excess airflow at idle.
Unmetered air entering past the throttle plate raises idle speed; common sources include cracked hoses, intake manifold gaskets, or brake booster diaphragm.
Carbon buildup or mechanical failure can prevent the valve from closing fully, allowing excessive bypass air.
Carbon deposits on the throttle plate or shaft can prevent full closure, increasing minimum airflow.
A stuck-open PCV valve or disconnected hose introduces unmetered crankcase vapors into the intake.
An erratic or out-of-range TPS voltage can cause the ECM to command a higher idle target.
Rare; only considered after all mechanical and sensor issues are ruled out and a known software update exists.
It is extremely uncommon. The code is almost always caused by a vacuum leak, IAC valve issue, or throttle body contamination. ECM replacement should only be considered after all other causes are eliminated and a manufacturer service bulletin confirms a software issue.
If the throttle plate is carbon-fouled and not closing fully, cleaning often resolves the code. However, if a vacuum leak or IAC fault exists, cleaning alone will not cure the problem.
The vehicle can typically be driven, but high idle may cause harsh engagement of the transmission, reduced braking assist, and increased fuel consumption. Prompt diagnosis is recommended.
Not necessarily. The valve may only be contaminated and respond to cleaning. Replacement is warranted only if cleaning fails to restore proper operation or the valve is mechanically damaged.