Code result
P0507
Idle Air Control System RPM Higher Than Expected
Moderate severity
What it means
Idle RPM exceeds the target despite the IAC commanded fully closed. Almost always caused by a vacuum leak that lets air bypass the IAC — torn intake hose, leaking PCV, brake booster, or intake manifold gasket.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Vacuum leak bypassing IAC
highOne of the most commonly reported causes for this code — check this first.
PCV valve stuck open
mediumA plausible cause — test and verify before replacing parts.
Brake booster diaphragm leaking
mediumA plausible cause — test and verify before replacing parts.
Related help
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