Code result
P0391
Camshaft Position Sensor B Circuit Range/Performance
High severity
What it means
Cam sensor B on bank 2 reads in range but plausibility check fails — slow response, drift, or signal does not match expected cam profile.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Sensor drift
highOne of the most commonly reported causes for this code — check this first.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Sensor mounting loose - signal damping
lowLess common, but worth ruling out after the more likely causes.
Related help
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