P0333: Knock/Combustion Vibration Sensor B Circuit High
What to do
Expect reduced performance and worse economy from continuously retarded timing.
What this code means
Sensor B's signal is above its expected range — a short to supply, or excessive noise. As with bank 1, persistent high readings make the module retard timing continuously, producing a flat and thirsty engine.
Likely causes
Start here
- Faulty knock sensor · moderate
- Wiring shorted to voltage · moderate
- Loose heat shield or bracket producing noise · easy
Less common
- Damaged sensor cable shielding · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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