2019 Mazda P0325: What It Means & Is It Safe to Drive?
P0325 on the 2019 Mazda: 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 2019 Mazda
- 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 2019 Mazda, repairs for P0325 typically fall between $150 and $500, depending on the root cause and labor rates in your area.
Known issues on Mazda
Mazda P0325 on SkyActiv-G engines is uncommon—these engines have robust knock sensor systems. When P0325 appears, check the sensor mounting torque first (SkyActiv knock sensors require 17–20 Nm torque to read correctly; under- or over-torqued sensors give incorrect signals or set P0325). On older Mazda3 2.3L (L3-VE) and Mazda6 2.3L, P0325 is more common due to heat-related harness degradation near the exhaust. On Mazdaspeed3 2.3T, a functional knock sensor is critical—do not drive with P0325 on a turbocharged Mazda.
Most commonly affected models