Check Engine Code
P0340
Camshaft Position Sensor A Circuit Malfunction (Bank 1 or Single Sensor)
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.
Symptoms that match P0340
If you got here from a search query, one of these might describe what your car is actually doing:
Recommended parts & tools for P0340
Most common fix for P0340:
Camshaft position sensorOur buyer’s guides cover the tools and parts that pair with AXLY:
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