P0088 Fuel rail pressure too high.

[Hessles]

Hi,

Quick back story; recently had my CFCA rebuilt, popped it back in the van and had an oil pressure issue. Drove spot on but occasionally flashed up about the oil pressure when hot. Engine came back out and went back to the builders to change the oil pump.

Oil pressure is now spot on but I have a different issue with too high fuel pressure. The only thing I changed was the leak down pipe (for an aftermarket jobbie) as I broke one of the connectors.

Is this likely to be the issue? Shall I swap over the (presumed) non return valve which looks a lot smaller on the aftermarket item?

I have VCDS and can see the rail pressure is higher than the expected value.

The van idles fine but won’t rev over 2k ish unless you work up to it slowly, if you give it some stick it’s like it hits a wall.

Any help with VCDS would be great before I throw the parts cannon at it!

 

[Hessles]

A couple of screen shots

 

[DXX]

The ‘check valve’ you mentioned is a pressure retention valve ‘h’ according to the diagram for a CFCA.
Replacing aftermarket with OEM would seem like a good starting point if the problem started straight after you installed the aftermarket part.

 

[Hessles]

For future reference of anyone searching. Cheap leak down pipes can cause this issue. I slapped the original one back on and it’s back to normal, lesson learned.

 

[DXX]

I’m a bit surprised that the diagram shows the rail pressure regulator drain line T into the injector leak line, seems like a uneccesary potential problem when two separate return lines would be fairly simple.
Anyway it seems to work.