Code result
P050B
Cold Start Ignition Timing Performance
Moderate severity
What it means
During cold-start the ECU retards ignition timing to raise exhaust temperature for catalyst light-off. The strategy does not deliver the expected timing - feedback from knock sensor or combustion model shows ignition too far advanced or retarded for the demanded calibration.
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
Knock sensor drift causes wrong feedback
highOne of the most commonly reported causes for this code — check this first.
Cam phaser offset against crank
mediumA plausible cause — test and verify before replacing parts.
Related help
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