P2350Cylinder 9 Pressure Variation High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2350 is the opposite of P234F: the cylinder 9 pressure signal swings more than plausible, with peaks or steps that do not fit the engine's operating state. No manufacturer publishes the code for cylinder 9. The analogue in Saab's 9-5 diesel workshop data is P039D, labelled as excessive pressure variation for cylinder 1, set as soon as the signal is outside its window for over 0.2 s and treated as a signal performance fault of Type B. A noisy signal comes mostly from the electrical side – interference on an unshielded or chafed signal wire, poor ground, failing sensor electronics. Less often the combustion itself is uneven, for instance through an injector that dribbles after closing. CARB requires such rationality checks of input sensors. Drivers rarely notice anything beyond the MIL.
- What you may notice
- Check engine light on
- Usually no noticeable symptoms
- Likely causes
- PossibleInterference or chafing on the sensor signal wire
- PossiblePoor sensor ground connection
- PossibleSensor electronics in the glow plug failing
- RareInjector of cylinder 9 dribbling after closing
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €100 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.