P0332: The knock sensor circuit on Bank 2 is reading too low
Knock Sensor 2 Circuit Low Input (Bank 2)
The bank 2 knock sensor signal is too low, so the engine cuts timing as a precaution. Get it checked within a week and do not use lower-octane fuel than recommended. If you hear knocking, stop driving.
Stop driving and get help if
- The check engine light is flashing
- The temperature gauge runs high, or you see steam (overheating)
- The car loses power, hesitates badly or stalls
- You smell burning or see smoke
- A brake warning light comes on, or the brakes feel different
Pull over as soon as you can, turn the engine off, and call a tow or roadside help.
What it means
P0332 is a Bank 2 specific knock sensor fault that indicates the sensor circuit voltage is below the expected threshold. This only appears on V6, V8, or other multi-bank engines. The knock sensor generates a small AC voltage signal when it vibrates. If the circuit input reads consistently low, the most likely cause is a short to ground in the signal wire, a dead sensor, or a broken reference circuit. With no knock feedback from Bank 2, the PCM cannot protect those cylinders from detonation damage and trims timing conservatively.
Common causes
- Short to ground in the Bank 2 knock sensor signal wireDamaged insulation on the signal wire allows it to contact the block or a ground point, pulling the signal low.
- Failed Bank 2 knock sensorThe sensor piezoelectric element fails and outputs a low or zero voltage signal.
- Corroded or damaged sensor connector on Bank 2Pin corrosion causes high resistance, which the PCM interprets as a low-signal condition.
- Loose Bank 2 knock sensorTorque spec matters. A loose sensor does not make proper contact with the block and generates no signal.
What the fix could involve
From the cheaper fix to the bigger one. Prices depend on your car, your area and the shop, so ask for a written quote that names the part and the labor before you approve it.
- Wiring or connector repair
- Knock sensor replacement (Bank 2)
- Knock sensor under intake manifold
Symptoms
- Check engine light on, steady
- Reduced power and throttle response on Bank 2 cylinders
- Worse fuel economy
- Possible audible knock under hard acceleration if true detonation is occurring
What to do next
If P0325 is also set, both banks are affected and you should check the wiring harness for a common damage point. If P0332 is alone, focus on the Bank 2 sensor and its wiring. On many GM V6 and V8 engines, both knock sensors are located under the intake manifold. The repair cost is mostly labor. Inspect the harness for chafing near the block first before committing to manifold removal.
Lewis reads P0332 alongside any Bank 1 knock sensor codes and shows live ignition timing, so you can see how the engine computer is compensating. Get Lewis on the App Store or Google Play.
Related codes
FAQ
- Is P0332 the same as P0330?
- Similar but different. P0330 is a general circuit malfunction on Bank 2. P0332 specifically reports a low-voltage input, pointing toward a short to ground or a dead sensor.
- Can I damage the engine by ignoring P0332?
- Yes, over time. Without knock detection on Bank 2, actual detonation goes undetected. Sustained detonation damages pistons, rings, and bearings.
- Does P0332 affect all cylinders or just Bank 2?
- Just the Bank 2 cylinders. Bank 1 knock detection is handled by a separate sensor and circuit.
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