OBD-II code · Powertrain (generic)
P0266 Cylinder 2 Contribution/Balance Fault
The ECU compares each cylinder's contribution to crankshaft speed (rough run analysis) and determined cylinder 2 contributes less or more than the average. This points to a mechanical or fuel delivery problem rather than a pure ignition fault.
Is it safe to drive with P0266?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyInjector clogged or worn
- PossibleLow compression on cylinder
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–6 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Fuel Injector, Cylinder Compression
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.