P0340: Camshaft Position Sensor A Circuit Bank 1 or Single Sensor
Do not keep driving
Expect extended cranking before starting, or a no-start. If the car eventually starts and then runs acceptably, that pattern points at cylinder identification rather than at fuel or spark supply.
What this code means
A circuit fault in the bank 1 camshaft position sensor. Where the crankshaft sensor supplies engine speed, the camshaft sensor supplies cylinder identification — which cylinder is on which stroke. Without it, sequential injection cannot be sequenced and the module may fall back to firing all injectors together, or refuse to start at all. Many engines will start and run on the crankshaft signal alone after a longer crank, which is itself a diagnostic clue.
Likely causes
Start here
- Faulty camshaft position sensor · moderate
- Corroded or loose connector · easy
- Open circuit in sensor wiring · moderate
Less common
- Low or dirty engine oil · easy
- Damaged reluctor or tone ring · specialist
Rare
- Failed control module · specialist
Symptoms
Components involved
Information, not instruction
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Community experience
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