P1199 | P0266 Citroen Jumper / Relay 2.0 BlueHDi 2018

[Jumper2018-2-0HDi]

Hello, good evening,

I can’t get rid of 2 fault codes after trying everything I can think of, and I'll be grateful for any advice.

I have a 2018 Citroen Jumper / Relay 2.0 BlueHDi 120 kW, which constantly gives me fault code P1199 = Fuel circuit : Incoherence on the reserve fuel pressure (Nearing no fuel). This fault code is persistent and cannot be cleared.

Additionally, I keep getting the P0266 fault code - Cylinder 2 Contribution/Balance Fault. While this one could be cleared, it reappears after a few starts and is accompanied by the engine revving to 1200 RPM.

The engine has newly reconditioned and coded injectors, a new rail pressure sensor, a new fuel filter, and has been inspected by an auto electrician for wiring to the injectors. Even after swapping injectors between cylinders, the P0266 fault code consistently appears on the second cylinder.

Does anyone have an idea what could be the cause?

Thank you all

[Chegutupaul]

You've eliminated the fact that it could be the injector by swapping them over. P1199 is likely related.

It could be that the fuel pressure getting to no.2 is off because of whatever is causing P1199. So there's enough fuel pressure for 3 cylinders not 4.

If you have diagbox you should be able to see readings you are getting in the

'standard parameter measurement'
' Info Fuel Circuit'

It may help you isolate the problem.

But I suspect low fuel pressure P1199 is causing P0266.
I would start by changing the fuel filter.

I've attached the code symptoms sheet for a C4 picasso, but I imagine it's similar for your boxer.

Hope this helps.