P0344: Camshaft sensor A, bank 1/single sensor: circuit intermittent.
Meaning, symptoms, causes and checks
P0344 concerns CMP A intermittent signal loss on bank 1 or the single sensor. A is normally intake on dual-cam engines; verify OEM identification. A circuit code does not automatically prove incorrect mechanical timing.
Affected system: Powertrain
Symptoms
- Extended/hard starting, sometimes stalling.
- Engine lamp, reduced power or fallback operation.
Possible causes
- Loose contact, internally broken wire or heat-damaged harness.
- Intermittent sensor/target fault, interference or unstable supply.
What to check
- Record P0344, freeze-frame and CKP/VVT/correlation codes; establish permanent versus temperature-related failure.
- Locate bank 1 sensor A or the single sensor using engine documentation.
- Inspect sensor, pins and head-area wiring; identify sensor design before measurement.
- Monitor signal/supply during the symptom and safely test accessible harness sections.
- Compare sensor/ECM waveforms; repair the proven circuit fault and confirm feedback before replacing the sensor.
Also written as: P0344-00, P034400, PO344 (some scan tools add the fault-type byte, e.g. -00).