What does code P0325 mean on a Pontiac and is it safe to drive?
P0325: Knock Sensor 1 Circuit Malfunction (Bank 1). Here's what it means on your Pontiac, what usually causes it, what repairs typically cost, and how safe it is to keep driving.
What this code means
The PCM isn't receiving a valid signal from knock sensor 1. Without knock feedback, the PCM retards ignition timing as a safety measure, reducing power and economy.
Common causes for your Pontiac
- Failed knock sensor
- Corroded or broken wiring/connector at the sensor
- Actual engine knock from carbon buildup or low-octane fuel
Symptoms
- Check Engine Light
- Reduced power and fuel economy (PCM retards timing)
- Possible audible knock or ping under load
Typical fixes
- Replace knock sensor
- Repair wiring and connector
- Use correct octane fuel and address carbon buildup
Repair cost range
For a Pontiac, repairs for P0325 often fall between $150 and $500, depending on the cause and whether you use OEM or aftermarket parts. Labor rates vary by location.
Known issues on Pontiac
Pontiac G6 3.5L/3.9L V6 (LX9/LZ4)—knock sensor is mounted on the engine block and accessible after removing the intake manifold upper plenum. The harness connector corrodes from moisture trapped under the intake. On G8 6.0L LS2 V8, P0325 is uncommon; check both bank sensors (P0325 = Bank 1, P0330 = Bank 2) and inspect the harness for heat damage near the exhaust manifold. Pontiac Firebird 3.8L Series II uses a piezoelectric knock sensor—connector corrosion is the typical failure; replace the connector and sensor as a pair.
Most commonly affected models