I have a little fabia with the 1.2 BZG engine and I've been having a bit of trouble with its running I have a fault P0171 Fuel trim,Bank1 system too lean (short circuit to B+) and its flagging up faults for the fuel pump, lambda sensor, solenoid valve n80 etc but all showing the same fault code and fault (as said above). I have put a new lambda sensor and engine Ecu on it but still have the same fault. Has anybody seen this before or can help? Thanks

I think there are 2 lambda probes, one pre cat and another post cat.

Open short circuit to B+ is a disconnected wire on blown fuse. I would imagine all of the above faults come from one source so need to check the current flow diagram for the vehicle and see what connects them. Worth checking the fuses meanwhile.

Fuel pump relay is the supplier, I think.

It's what I had in the back of my mind. But is that separate from the central electrics controller?

Yeah I found the fuel pump relay to be 'clicking' when being activated. I replaced the wires from the lambda to the engine Ecu to eliminate that wiring. The fault is for G39 so before the cat sensor. So do you think it could be a wire from the relay to the fuse bar on the top of the battery?

If you clear codes does it all come back?

Yeah clear the codes and they come back on a long roadtest. Sometimes when starting the vehicle it's a wee bit sluggish for a second or 2

Check the in tank fuel pump output pressure. If it's not 4bar+ then that's your issue.