54 reg. 135ps TDCi Empty fuel filter

[Westline]

I hope someone can shed some light on this problem. The van, a 135 ps Jumbo with 196000 on the clock had a new fuel filter fitted about 6k miles ago. It was done the usual way, the filter filled before fitting and the van started first time. Since then, when the van has been stood for a long time, it starts and then dies. Restarting takes a few seconds and then it runs fine.
Next. It went in for a couple of new rockers and a blowing exhaust manifold to be fitted. This as you know needs the injector pipes off and afterwards it was a right bugger to bleed up and to get running. The following day the van was leaving blue smoke, the management light came on and then it cut out. It would immediately restart, no cranking and the fault would clear only for it to do it again. The smoke was traced to a leak on the return pipes off the injectors and this was replaced curing the smoke but not the cutting out.
We stripped off the injector loom and cleaned everything off but the same cutting out continued. Every time it went under load or over 2500 rpm it would go to limp mode. Sometimes cutting out, sometimes not but each time you turn the ignition off and on the fault would clear. The was also a lot of diesel knock which I always thought meant a weak mixture.
It was then scanned and low fuel pressure was diagnosed. We then decided to change the fuel filter as a precaution only to find that it was empty. I mean there was only a very small amount in the bottom. Very strange. I thought it might be the lift pump in the tank only to find that it hasn't got one. We noticed too, a lot of bubbles in the pop out thingy that is supposed to tell you to change the filter. So we stripped off this pipe and checked that but it still didn't cure it. We changed the filter head and the filter too but it still ended up emptying. Oh and it ticks over lumpy. The van will rev its head off without problem but under load. Straight to limp home.
Sorry to be long winded but it's a long winded problem. I don't want to condemn the fuel pump yet. It cost too much. And I don't thnk it can be the ECU as that wouldn't explain the fuel filter emptying.

Any ideas chaps before I throw it off a cliff and but a VW

Michael

[fedup2]

did you shed any light on this?
my fuel filter seems not to be running at full.