What does code P0340 mean on a Mazda and is it safe to drive?
P0340: Camshaft Position Sensor Circuit Malfunction. Here's what it means on your Mazda, what usually causes it, what repairs typically cost, and how safe it is to keep driving.
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What this code means
The PCM is not receiving a valid signal from the camshaft position sensor. Affects ignition timing and fuel injection.
Common causes for your Mazda
- Failed camshaft position sensor
- Wiring or connector issue
- Timing chain/belt misalignment (less common)
Symptoms
- Check Engine Light
- No start or hard start
- Rough run, stalling
- Reduced power
Typical fixes
- Replace camshaft position sensor
- Repair wiring/connector
- Verify timing if sensor replacement doesn't fix
Repair cost range
For a Mazda, repairs for P0340 often fall between $100 and $500, depending on the cause and whether you use OEM or aftermarket parts. Labor rates vary by location.
Known issues on Mazda
Mazda MZR-engine P0340 usually means a failed cam position sensor or a dirty reluctor ring. Inspect the sensor O-ring for oil leakage. On SKYACTIV-G engines, a timing chain stretch can cause the cam sensor signal to fall out of expected range.
Most commonly affected models
Mazda3 2.0L/2.5L 2004–2013Mazda6 2.3L/2.5L 2003–2013CX-5 2.0L/2.5L 2013–2016