P0340: Camshaft Position Sensor 'A' Circuit Malfunction (Bank 1 or Single Sensor)
What this check-engine code means in plain English, what usually causes it, and what a fix typically costs.
What P0340 means
The engine control module (ECM) has detected a problem with the camshaft position sensor circuit on Bank 1. This sensor tells the computer the exact position of the camshaft so it can time fuel injection and ignition properly. When the signal is missing, erratic, or out of range, the check engine light comes on and the engine may run poorly or not start at all.
What causes P0340?
Is P0340 safe to drive?
Driving is not recommended because the engine may stall without warning, run extremely rough, or fail to restart once turned off. If the underlying cause is a timing chain or belt problem, continued operation can lead to catastrophic engine damage.
P0340 repair cost
Industry-average estimates. Cost depends on whether it's just the sensor and connector or requires timing component inspection and labor-intensive access.
Which one is it for your car?
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