Code result
P239D
Diesel Intake Air Flow B Control System Low Air Flow Detected
Moderate severity
What it means
Same as P239C with the airflow below the threshold when the valve is commanded open - valve does not open fully or the path is restricted.
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 open fully
highOne of the most commonly reported causes for this code — check this first.
Related help
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