2016 Subaru P0325: What It Means & Is It Safe to Drive?
P0325 on the 2016 Subaru: Knock Sensor 1 Circuit Malfunction (Bank 1). Here's what it means, what usually causes it, what repairs typically cost, and whether it's safe 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 on the 2016 Subaru
- 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 2016 Subaru, repairs for P0325 typically fall between $150 and $500, depending on the root cause and labor rates in your area.
Known issues on Subaru
Subaru P0325 on EJ25 SOHC engines is often a wiring harness issue—the knock sensor harness runs near the downpipe and exhaust, causing heat damage to the insulation over time. Inspect the entire harness length from sensor to PCM connector. On EJ257 turbocharged (WRX STI), a non-functional knock sensor is a critical issue—the Subaru ECU retards timing significantly when knock is detected under boost, and if the sensor is dead, the engine is unprotected from detonation. Fix immediately on turbocharged applications.
Most commonly affected models