OBD-II code · Powertrain (generic, extended)
P20D8 Exhaust Aftertreatment Fuel Supply Control Performance
Aftertreatment fuel supply is electrically OK but does not deliver the commanded pressure or flow during regeneration — weak pump or partial blockage.
Is it safe to drive with P20D8?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyPump weak — flow or pressure below threshold
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.7–3.5 h
- Emissions test
- Likely to fail
- Parts involved
- Aftertreatment Fuel Pump
Related codes
- P20D7Exhaust Aftertreatment Fuel Supply Control Circuit/Open
- P20D5Exhaust Aftertreatment Fuel Injector B Stuck Open
- P20D6Exhaust Aftertreatment Fuel Injector B Stuck Closed
- P20D9Exhaust Aftertreatment Fuel Supply Control Circuit Low
- P20DAExhaust Aftertreatment Fuel Supply Control Circuit High
- P20DBExhaust Aftertreatment Fuel Supply Control Stuck Open
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.