engine cuts out,help

Hi Guys my disco 2.5 tdi keeps cutting out at or after high revs, I think it may be fuel starvation cos it ticks over ok. I've put new fuel lines, new lift pump and bled the fuel system a few times.
When reved high there is lots of smoke and it cuts out but ticks over ok.
Any ideas guys as I am baffled

What engine is it??
What colour is the smoke??

Does sound like there is air in the fuel lines.... on disco's a good place to check is the fuel lift elbows on the top of the fuel tank - underneath the carpet in the boot (under the round inspection cover) and you should check the fuel sedimentor

Hi mate, checked all of those places like you say and there ok, its a 2.5 tdi 300, smoke is a light blue colour, it happened like this ages ago when i put the tank back in and that was air but now started again

The fuel lift elbows on top of the tank can be porous and allow air into the fuel lines as can the sedimentor. It only has to be a pin hole for the air to get in - you won't see fuel leaking out usually either - most people bypass/remove the sedimentor as if its not sealed correctly it will allow air in too

To narrow down the search for the air leak: put some clear fuel pipe inbetween fuel tank and lift pump and between lift pump and filter and between filter and injection pump - you will be able to see the bubbles in the clear pipe and it will indicate at what point the air is getting in

Hi Mate the sedimenter has been by passed when I put new fuel lines from the tank to the engine and injection pump

I'd start with the clear fuel pipe then mate - you only need a couple of inches inbetween the tank/lift pump and lift pump/filter and filter/injection pump but if you have replaced the fuel lines from the tank and disturbed the tank i would be looking at the fuel connections at the fuel tank

I've got it running ok now, but have blue smoke, if that means too rich fuel how do I turn it down to weaken the mixture

HI GUYS, the engine was running ok but cut out, so I suspected the lift pump had gone so I bought another and surprise it still didn't go. With a lot a mucking about I found that when I undid the second injector union from the windscreen end . the engine started and ran but tighten the nut and it cut out.
Any ideas cos its really starting to bug the hell out of me.HELP

Well still got no clues here, anybody help me

Did you try the clear fuel pipe as suggested?