Thread: Fault Codes U2023 and P0087

Fuel filter, LPFP and HPFP are all possible suspects, in order of cost. The LPFP is in the tank.
Have a read of this:
DISCO3.CO.UK - View topic - Robbie's Guide To The Low Pressure Fuel System

Scott

Originally Posted by Lukeis

Hi Gents

Tonight while driving home I received the above fault codes, lost significant amount of power and the lights "Gearbox error" and "Restricted Performance" illuminated on the dash.

Ive read the codes as follows:

U2023 - Gearbox - control module network signal calibration data
P0087 - Engine Management - Fuel rail/system pressure - too low

Was hoping for suggestions of things to do/check tomorrow..

1) Replace fuel filter
2) Check battery voltage
3) is there a fuel pump filter? if so, where is it?
4) anything else I can check myself?

What was the outcome I have the same errors?

Originally Posted by orville

What was the outcome I have the same errors?

Want to borrow my fuel pressure gauge? I cable-tied it to the windscreen wiper and drove until it faulted. That ruled out the LPFP & Filter, leaving only the HPFP as the potential culprit.

I have a gauge, I bought one to test lpfp. I guess the outcome is obvious, trying to eliminate everything before jumping into a new hpfp.

Originally Posted by orville

I have a gauge, I bought one to test lpfp. I guess the outcome is obvious, trying to eliminate everything before jumping into a new hpfp.

As mine was all but undriveable last week, I "tickled" the PCV on the HPFP last Saturday which put the fault into remission for about 500k's, but it came back last night. I have a few other things to try, but I know ultimately it's going to need a new pump. I'm just prolonging the inevitable while trying to get a more detailed understanding of the exact failure mechanism.

Thanks for the feedback, I will pass it on to my son. I have trawled the internet for ideas and found nothing. Even looked at Ford and Peugeot motors. Read discussions about the merits of two stroke oil (snake oil?) . I think he is going to take out the lpfp and clean the filter as a possibility.

Originally Posted by orville

Thanks for the feedback, I will pass it on to my son. I have trawled the internet for ideas and found nothing. Even looked at Ford and Peugeot motors. Read discussions about the merits of two stroke oil (snake oil?) . I think he is going to take out the lpfp and clean the filter as a possibility.

Which is why I suggested using the gauge. You can actually watch the low-side pressure as the fault occurs. If it doesn't move (like mine) then there would be no point dropping the tank to get the LPFP out and you'd rule out the filter and associated pipework at the same time. Of course if the low-side pressure tanks as the fault occurs then you have more reason to tear into the fuel supply system.

I will try your idea.