Code result
P2391
Diesel Intake Air Flow B Control Performance
Moderate severity
What it means
Same as P2390 with the actuator electrically intact yet not delivering the commanded position - sticky valve, broken linkage, or position 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 stuck due to soot
highOne of the most commonly reported causes for this code — check this first.
Related help
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