P03D9
Cylinder 7 Pressure Variation High
Cylinder-to-cylinder pressure variation on cylinder 7 is above the calibrated maximum — combustion is unstable cycle-to-cycle, typical of partial misfire or injector seat erosion.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
Common causes
Ordered by how often each turns out to be the cause.
- Partial misfireCommon
Parts involved
- Cylinder Pressure Sensor
P03D9 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.