Idle Control System RPM High
What does P0507 mean?
The P0507 code means the vehicle's onboard diagnostic system has detected: Idle Control System RPM High. This is a moderate severity code.
Common Symptoms
- Idle speed too high (above 1,000 RPM warm)
- Check Engine Light on
- Engine does not return to normal idle after acceleration
Probable Causes (Ranked by Likelihood)
- Vacuum leak allowing extra air into the intake at idle Very High
- Stuck open IAC valve or throttle body bypass air passage High
- Throttle body gasket leak Moderate
- Carbon buildup holding throttle plate partially open Moderate
Step-by-Step Diagnostic Procedure
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Check for vacuum leaks systematically -- a high idle almost always indicates unmetered air entering the intake.
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Inspect the throttle body for carbon preventing full throttle closure.
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Command the IAC valve to a low step count with a scan tool. If idle does not drop, the valve is stuck or a vacuum leak is dominating.
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Inspect the PCV system -- a stuck-open PCV valve or damaged PCV hose is a common unnoticed vacuum leak.
Frequently Asked Questions
My car idles at 1,500 RPM when warm -- is that always P0507?
Not necessarily. A high idle can be caused by a vacuum leak even without a stored code. P0507 stores when the ECU has lost the ability to control idle speed. Check for vacuum leaks first regardless of whether a code is present.