P0339
Crankshaft Position Sensor A Circuit Intermittent
The crankshaft position sensor A signal jumps or drops out intermittently — connector, sensor air gap, or damaged tone wheel. The PCM may detect a "false" stall or misfire spike when the signal drops.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Intermittent connectorCommon
- Tone wheel chipped or contaminatedPossible
- Connector with intermittent contact under vibrationLess likely
Parts involved
- Crankshaft Position Sensor
- Flywheel
P0339 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.