P34BD
B Camshaft Position Actuator Position Sensor A Range/Performance Bank 1
Position sensor of exhaust cam actuator on bank 1 reads implausibly compared to commanded position. The camshaft position sensor identifies which cylinder is on the compression stroke — without it the ECM cannot run sequential injection or coil-on-plug ignition correctly.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
Symptoms
- Check engine light on
- Power loss especially in mid-rpm range
- Possible rough idle or stalling
- Increased fuel consumption
Common causes
Ordered by how often each turns out to be the cause.
- Sensor reading driftedCommon
- Sensor element aged beyond calibration windowLess likely
- Sensor mounting loose - signal dampingLess likely
Parts involved
- Cam Actuator B Pos Sensor B1
P34BD is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.