Trouble code
P0325
Knock Sensor 1 Circuit Malfunction (Bank 1)
What P0325 means
The knock sensor circuit is out of range. The computer uses this sensor to detect detonation and retard timing to protect the engine.
Symptoms you may notice
- Reduced power
- Worse fuel economy
- Pinging under load
Common causes, cheapest first
- Failed knock sensor
- Corroded connector or wiring
- Sensor not torqued correctly after previous work
Before you buy anythingOn many V6 and V8 engines the knock sensors sit under the intake manifold, so the part is cheap and the labor is not. Buy a quality sensor, because doing that job twice is the expensive outcome.
What to do next
- Confirm the code with your own scan tool, or have it read free at a chain parts store.
- Decode your VIN so you know your exact engine and build date.
- Work down the causes above from cheapest to most expensive.
- Search NHTSA for a recall or service bulletin covering this symptom on your vehicle.
- Read the ignition buying guide before ordering.
P0325 is a generic OBD-II code, standardized across every make and model sold in the US from 1996 onward. The meaning is the same on any vehicle; the specific part and its location are not.
Parts
Parts commonly needed for P0325
These go to Amazon. We earn a commission if you buy, at no extra cost to you — see our affiliate disclosure. Which one you actually need depends on diagnosis — read the note above first.
Confirm fitment against your VIN on the listing page before ordering. A part that matches your year and model can still be wrong for your build date or engine code.