OBD-II code · Powertrain (generic)
P0291 Cylinder 11 Injector A Circuit Low
Cylinder 11 injector A control voltage below expected range. A flow-deviating injector throws off cylinder balance — adjacent cylinders run leaner/richer to compensate, often masking the root cause until the trim limit is hit.
Is it safe to drive with P0291?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyWiring shorted to ground
- Less likelyConnector pins corroded - high contact resistance
- Less likelyHarness chafing through insulation
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.5–2 h
- Emissions test
- Likely to fail
- Parts involved
- Injector Cyl11, Injector Wiring
Related codes
- P0276Cylinder 6 Injector A Circuit Low
- P0279Cylinder 7 Injector A Circuit Low
- P0282Cylinder 8 Injector A Circuit Low
- P0285Cylinder 9 Injector A Circuit Low
- P0288Cylinder 10 Injector A Circuit Low
- P0294Cylinder 12 Injector A Circuit Low
- P21DBCylinder 1 Injector B Circuit Low
- P21DECylinder 2 Injector B Circuit Low
- P21E0Cylinder 3 Injector B Circuit Low
- P21E2Cylinder 4 Injector B Circuit Low
- P21E4Cylinder 5 Injector B Circuit Low
- P21E6Cylinder 6 Injector B Circuit Low
- P028ECharge Air Cooler Cooling Fan Control Circuit High
- P028FCharge Air Cooler Cooling Fan Control Circuit Driver Performance
- P0290Cylinder 10 Contribution/Balance
- P0292Cylinder 11 Injector A Circuit High
- P0293Cylinder 11 Contribution/Balance
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.