Code result
P0506
Idle Air Control System RPM Lower Than Expected
Moderate severity
What it means
The engine idles below the target RPM despite the IAC opening fully. Indicates restricted air path past the IAC — typically a heavily fouled throttle body or stuck IAC valve.
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
Throttle body or idle bypass passage clogged
highOne of the most commonly reported causes for this code — check this first.
IAC valve stuck mostly closed
mediumA plausible cause — test and verify before replacing parts.
Related help
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