What does code P0325 mean on a Volvo and is it safe to drive?
P0325: Knock Sensor 1 Circuit Malfunction (Bank 1). Here's what it means on your Volvo, 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 Volvo
- 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 Volvo, 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 Volvo
Volvo P0325 on B5254T T5 inline-five engines—the knock sensor is mounted on the block and the wiring harness routes along the top of the engine. Connector corrosion and harness chafing near the intake manifold are the primary causes. On Polestar-tuned T5 and T6 engines, the knock sensor retard strategies are actively used—a faulty sensor can prevent the Polestar tune from running at optimal timing. On turbocharged Drive-E 2.0T engines (2015+), P0325 combined with P0299 (underboost) may indicate a loose sensor on a turbocharged block resonating incorrectly.
Most commonly affected models