P0327 Code: Knock Sensor Low — Causes & Fix
P0327 means the knock sensor circuit (bank 1) signal is too low — the sensor that detects engine detonation so the ECM can retard timing.
- Applies to
- All OBD-II vehicles (any make or model)
- Est. repair cost
- $40 – $500
- Time to fix
- 30 minutes – 2 hours
What it means
Common causes are a failed knock sensor, a loose sensor, or wiring/connector faults. P0327 is a generic OBD-II powertrain code defined in the SAE J2012 standard, so it applies to virtually any 1996-or-newer petrol car or light truck regardless of make. Fix the underlying fault, then clear the code with an OBD-II scan tool — it will return if the problem isn't resolved.
Symptoms
- Check engine light on
- Reduced performance (timing pulled back)
- Possible pinging under load
How to fix it
- 1
Inspect the knock sensor and wiring
1. Locate the knock sensor on the engine block. 2. Check that it is torqued correctly and the connector is clean.
- 2
Test or replace the sensor
1. Check the sensor circuit resistance against spec. 2. Replace if faulty, then clear the code.
Frequently asked questions
Will P0327 hurt my engine?
Not directly, but with the knock sensor out the ECM may run more conservative timing (less power) or miss real knock. Fix it to keep protection working.
Last updated July 19, 2026
Guidance only — always consult a qualified professional or the official service manual before carrying out repairs.