Engine and gearbox (P)
P0340: Camshaft position sensor circuit
The engine control unit is not receiving a proper signal from the camshaft position sensor. This can affect engine timing and performance.
Checked by a licensed car technician · last reviewed 29 September 2026
Symptoms
- Engine may not start
- Rough idling
- Reduced power
- Check engine light on
Common causes
- Faulty camshaft position sensor
- Damaged wiring or connectors
- Timing chain or belt issues
- Faulty engine control unit
How to check it yourself
- Inspect the camshaft position sensor for damage
- Check wiring and connectors for corrosion or damage
- Verify timing chain or belt alignment
- Test the engine control unit
Can I keep driving?
The car can be driven, but performance may be reduced. Have it checked soon.
General guidance, not a professional inspection. Confirm faults with measurements before buying parts, and use a qualified mechanic for brakes, steering, fuel leaks, airbags, and other safety-critical work. Terms and disclaimer