What does code P0325 mean on a Audi and is it safe to drive?
P0325: Knock Sensor 1 Circuit Malfunction (Bank 1). Here's what it means on your Audi, 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 Audi
- 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 Audi, 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 Audi
Audi P0325 on EA888 2.0T TFSI shares VW's knock sensor location and harness concerns. On S4 and A6 3.0T supercharged engines, the knock sensors are on the side of the block and accessible; vibration from the supercharger can eventually loosen the sensor mounting—check the torque first. On RS5 4.2 FSI V8, knock sensors are deeply recessed in the vee of the block. Audi recommends VCDS scan to read the knock sensor adaptation values—if adaptation is at maximum retard, investigate genuine detonation before assuming sensor fault.
Most commonly affected models