Powertrain
generic / SAE
P03B9
Cylinder 4 Pressure Too High
Cylinder 4 measured peak combustion pressure is above the calibrated maximum — typically pre-ignition, knock, over-fuelling, or runaway combustion.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number3 / B9
Possible causes
- Pre-ignition or knock high
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 400–4000 €
- Estimated time: 2–8 h
- Component: cylinder pressure sensor
- MIL / check engine light
- emissions-relevant
- limp mode possible
Sources
References
sae:J2012