P0340
Camshaft Position Sensor Circuit Malfunction
high
i Description
The Camshaft Position (CMP) sensor circuit has a malfunction. The CMP sensor tells the ECU the position of the camshaft, enabling sequential fuel injection and variable valve timing control.
? Common Causes
- Faulty CMP sensor
- Damaged wiring or connector
- Timing chain/belt has jumped
- Damaged reluctor wheel on camshaft
- ECU fault (rare)
! Symptoms
- Check engine light
- Hard starting or no-start
- Rough idle
- Reduced power
- Engine stalling
# Diagnostic Steps
- Check CMP sensor connector
- Test sensor signal with scan tool or oscilloscope
- Inspect wiring
- Verify timing chain/belt alignment
- Replace sensor if no signal
⚙ Typical Fix
Replace the camshaft position sensor. Check timing chain/belt if sensor is OK.
Parts Needed
Camshaft position sensor
Estimated Cost
$100-$400
↔ Related Codes
Q Frequently Asked Questions
The car may run poorly or not start at all. If it is running, drive carefully to a mechanic. The engine will default to batch injection mode.
CMP sensor: $30-$100. Labour: $50-$200. If the timing chain has jumped, the repair is significantly more expensive ($500-$2000).
☞ Learn More
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