P0340 — Camshaft Position Sensor A Circuit (Bank 1 or Single Sensor)
High severityWhat it means
P0340 is stored when the engine control unit sees a fault involving the camshaft position (CMP) sensor circuit. The camshaft position sensor lets the control unit identify which cylinder is on its firing stroke, which is needed for sequential injection and ignition. The control unit has flagged this circuit or signal as outside its normal operating range.
Common symptoms
- Hard starting or long cranking
- Stalling or misfire
- Reduced power
Likely causes
- A wiring, connector or ground problem in the circuit
- A failed sensor or actuator in the circuit
- Faulty camshaft position sensor
- Timing chain/belt wear or a VVT issue affecting cam timing
What to check first
- Inspect the connector and wiring for damage, corrosion or loose pins
- Inspect the sensor connector and wiring
- Check for cam/crank correlation codes and timing noise
Can you keep driving?
May cause hard starting or stalling; if it runs poorly or makes timing noise, avoid driving until checked.
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