P0281Cylinder 7 Contribution/Balance
- 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
- P0281 comes from the cylinder balance control of common-rail diesels: the engine module measures the crankshaft acceleration of each cylinder's power stroke, compares it with the average and gives a deviating cylinder more or less fuel. The code sets when the correction for cylinder 7 reaches its limit and the cylinder still does not keep up – GM at 95 % of a limit of about ±12–17 mm³ for 30 s, Ford above 90 % of the allowed 3.5–15 mg per stroke for 7.5 s; GM needs two trips. The code does not say whether there is too much or too little fuel – the correction value for cylinder 7 shows the direction: strongly negative means a leaking injector, strongly positive a weak injector or low compression.
- What you may notice
- Check engine light on
- Rough idle, shaking or knocking
- Loss of power or smoke
- Higher consumption, poor cold start
- Likely causes
- LikelyInjector of cylinder 7 worn, coked or leaking
- PossibleEngine software outdated or diagnosis too sensitive
- PossibleInjector correction codes not or wrongly programmed after replacement
- PossibleLow compression on cylinder 7 (valve, rings, injector seal)
- RareCrankshaft sensor or tone wheel learning faulty, dual-mass flywheel
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.