KlaroFault codeP2635
MODERATEFuel Pump A Low Flow/Performance
What this code means
Fuel Pump A Low Flow/Performance.
P2635 is a generic code: it means the same thing on every make. P2635 belongs to family P26xx — Control unit and auxiliary outputs. Its page explains how to read a code and groups all its codes by part.
Type of fault
The signal stays within its electrical limits, but its value is not plausible: it does not match what the control unit expects given the other sensors. The sensor may be drifting with age, but it may also be faithfully measuring a real mechanical problem — a leak, a blockage, an air leak. Replacing the sensor without checking does not always clear the fault.
Fuel pump
The fuel pump, usually inside the tank, sends fuel to the engine. The control unit switches it on through a relay or a control module, sometimes at several speeds, and may check its circuit.
What you notice
Hard starting, the engine cutting out under load, loss of power at high speed, or no start at all if the pump stops.
How to check it
Check the pump's fuse and relay first, then its connector, often on top of the tank under the rear seat or the boot floor. With ignition on, you should hear the pump run for a second or two. Klaro's fuel pressure reading, when the car reports it, shows whether pressure holds under load.
Watch it live in Klaro
With an OBD2 adapter plugged in, these live readings show the part at work, when your car reports them:
- Fuel pressure
- Fuel rail pressure (absolute)
- Fuel rail absolute pressure
What to do
Have it checked this week. The car remains usable, but the fault will not clear itself and will fail the roadworthiness test.
Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →
How to read this code
- PPowertrain
- 2standardised code
- 6Control unit and auxiliary outputs
- 35P2635
