P249EClosed Loop Reductant Injection Control At Limit - Flow Too 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
- P249E is the counterpart to P249D: here the SCR feedback has trimmed the dosing down to the lowest correction it is allowed, because more reductant seems to arrive than the NOx reading calls for. GM's 2014 diesel table flags a long-term adaptation factor below 0.41 (Type B); the 2018 table lists the low-side check as a two-trip Type B fault. Ford's 2023 summary uses the same 30 s clip rule as for P249D. A dosing valve that leaks or sticks partly open, overly concentrated fluid, ammonia slip being read by the NOx sensor as NOx, or a sensor that reads too low can all lead here. Ammonia smell at the tailpipe and white deposits around the injector are possible clues; drivability itself is rarely affected.
- What you may notice
- Malfunction indicator lamp on
- Ammonia smell from the exhaust
- White crystalline deposits at the dosing point
- Likely causes
- LikelyDosing valve leaking or sticking partly open
- PossibleAmmonia slip from an aged or overloaded SCR catalyst seen by the NOx sensor
- PossibleNOx sensor reading too low
- RareFluid concentration outside specification
- 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 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.