Code result
P239C
Diesel Intake Air Flow B Control System High Air Flow Detected
Moderate severity
What it means
With diesel intake air flow valve B commanded closed the measured airflow is above the calibrated threshold - valve does not seat or position sensor offset.
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
Valve does not seat fully
highOne of the most commonly reported causes for this code — check this first.
Related help
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