OBD-II code · Powertrain (generic, extended)
P2636 Fuel Pump B Low Flow/Performance
The second fuel pump runs but does not deliver expected volume or pressure. Worn pump, restricted filter, or leaking pressure regulator.
Is it safe to drive with P2636?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyWorn impeller reduces volumetric efficiency
- PossibleRestricted in-tank or in-line fuel filter
- PossiblePressure regulator leaks back to tank
Symptoms
- Check engine light on
- Hard start, no start, or stalling under load
- Power loss especially at high load or rpm
- Possible long cranking time
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Often, with basic tools
- Typical labour
- 1–4 h
- Emissions test
- Usually unaffected
- Parts involved
- Fuel Pump B, Fuel Filter, Fuel Pressure Regulator
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.