P21FDFuel Control System B Too Rich at Higher Load (Bank 1)
- 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
- P21FD sets when the second fuel path on bank 1 is still rich at higher load although its learned correction has already taken away the permitted maximum. No manufacturer documents the code publicly. The FCA patent for port plus direct injection engines describes three separate monitors, one per injection mode, so a rich error that appears only while the port system fuels alone can be pinned on that system rather than reported as a general P0172. Possible causes are an air mass sensor reading high at large airflow, a regulator in the low-pressure circuit holding too much pressure, or port injectors that over-deliver at long opening times. Higher fuel consumption and sooty tailpipes may follow. P2192 is the system A counterpart, P21FF the bank 2 code.
- What you may notice
- Check engine lamp on
- Increased consumption, sooty tailpipe
- Likely causes
- PossibleAir mass sensor reading too high at large airflow
- PossibleLow-pressure regulator holding too much pressure
- RarePort injectors on bank 1 over-delivering
- 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: €50 – €900
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.