P0325 Code: Knock Sensor 1 Circuit Malfunction (Bank 1)
🟠 Moderate severity · drivable
Drivable, but the computer may reduce performance (retard timing) to protect the engine, so fix it soon.
What P0325 means
The knock sensor on bank 1 isn't sending a proper signal. This sensor detects engine knock (pinging) so the computer can adjust ignition timing to prevent damage; without it, the computer can't protect the engine from knock.
Symptoms
- Check engine light is on
- Reduced power or acceleration
- Possible engine pinging or knocking
- Poor fuel economy
Common causes
- most common: Faulty knock sensor
- common: Damaged wiring or loose connector at the sensor
- less common: Engine mechanical noise confusing the sensor
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Inspect and clean the knock sensor connector | Yes | $0–10 |
| Replace the knock sensor | Yes | $50–200 |
| Repair damaged knock sensor wiring | Mechanic | $50–200 |
Frequently asked questions
Can I drive with a P0325 code?
Yes, but the engine can't protect itself from knock, and you may notice reduced power. Fix it soon.
What is the most common cause of P0325?
A faulty knock sensor. It's usually inexpensive and not too hard to reach.
How much does it cost to fix a P0325?
Typically $50–$200 for a new knock sensor.
Related codes
P0327
P0327 Code: Knock Sensor 1 Circuit Low Input (Bank 1)
P0328P0328 Code: Knock Sensor 1 Circuit High Input (Bank 1)
P0330P0330 Code: Knock Sensor 2 Circuit Malfunction (Bank 2)
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.