P0328: Knock/Combustion Vibration Sensor A Circuit High
What to do
Expect noticeably reduced performance and worse economy, since the engine will be running retarded timing continuously.
What this code means
Sensor A's signal is above its expected range — a short to supply, or excessive noise reaching the sensor. Persistent high readings cause the module to retard timing continuously, which is why the symptom is a flat, thirsty engine rather than an obvious fault.
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
- Corroded or loose connector · easy
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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