Check Engine Code
P0340
Camshaft Position Sensor A Circuit Malfunction (Bank 1 or Single Sensor)
Severity: high
DIY difficulty: 2/5
Typical cost: $50–$400
What P0340 means
The cam sensor pairs with the crank sensor to let the ECM know engine rotation position for sequential fuel injection and ignition. Without it, the engine often defaults to less efficient batch fire or refuses to start.
Symptoms
- Check engine light
- Hard starting or no start
- Stalling
- Loss of power
- Erratic idle
Likely causes (most common first)
- Failed cam position sensor
- Wiring or connector issue
- Damaged reluctor ring on the cam
- Metallic debris stuck to the sensor tip
Can I keep driving?
High — risk of damage if ignored
Typical repair cost
DIY fixes can start near $50 (parts only). Shop repairs for P0340 typically run up to $400 depending on the underlying cause and vehicle. Start with the most common cause — Failed cam position sensor — before throwing parts at it.
Related codes
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