OBD-II code · Powertrain (generic, extended)
P21C0 Cold Start Cylinder 11 Injection Timing
Cylinder 11 cold-start injection timing is outside the calibrated window. Diesel cold-start uses adapted injection timing per cylinder to limit white smoke and noise; deviation typically points at a worn injector or faulty crank/cam correlation.
Is it safe to drive with P21C0?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyInjector flow-rate aged
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–6 h
- Emissions test
- Likely to fail
- Parts involved
- Fuel Injector
Related codes
- P21B6Cold Start Cylinder 1 Injection Timing
- P21B7Cold Start Cylinder 2 Injection Timing
- P21B8Cold Start Cylinder 3 Injection Timing
- P21B9Cold Start Cylinder 4 Injection Timing
- P21BACold Start Cylinder 5 Injection Timing
- P21BBCold Start Cylinder 6 Injection Timing
- P21BCCold Start Cylinder 7 Injection Timing
- P21BDCold Start Cylinder 8 Injection Timing
- P21BECold Start Cylinder 9 Injection Timing
- P21BFCold Start Cylinder 10 Injection Timing
- P21C1Cold Start Cylinder 12 Injection Timing
- P21C2Reductant Heater Relay Control Circuit/Open
- P21C3Reductant Heater Relay Control Circuit Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.