300tdi power problem!!

Hi there new to this forum, basically I've got a problem that is tearing my hair out so hopefully I can get some answers on here.
P reg disco 1 300tdi auto, non edc. Replaced engine due to none repairable engine failure, new engine runs fine etc. My problem is that it seems to be lacking power. Its slowISH from 0-30mph, when you get to 30/40mph the car just gives up all hope of life and will take forever to even reach 60mph, there's is small amount (not major amounts just enough to notice it) of black smoke out the exhaust but more noticeable when pulling away from standstill. I have checked all of the obvious thats why I'm asking you geniuses hoping someone will give me answers before I burn the thing.

Cheers

Have you got turbo pressure at the manifold?
Is the boost pin working correctly and the little pin in the injector that sldies against it moving correctly?
Have you got boost pressure at the fuel pump?

Have you checked the timing?

Cheers

Not checked boost pressure at pump, but must be boost pressure at manifold as pipe swells when revving the engine. Not checked the timing as of yet, not got the correct pins at the moment and never really thought to check timing as the engine runs sweet apart from this strange power problem

Clarky321 said:

Not checked boost pressure at pump, but must be boost pressure at manifold as pipe swells when revving the engine. Not checked the timing as of yet, not got the correct pins at the moment and never really thought to check timing as the engine runs sweet apart from this strange power problem

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You need to check the pressure when the engine is under load. Not just revving when stationary on the drive.

Also check the throttle cable is not too loose and does not have lots of slack at the fuel pump.

Timing was really just a check to make sure.

Cheers

The only strange thing I've noticed is that fuel filter is only 3/4 full, no flow at feed pipe of injection pump but the engine doesn't seem to be being starved of fuel so I just ignored this. Another thing, the wastegate doesn't seem to move when revved when stationary, didnt know if it would move when stationary or if it would have to be underload.

Will plumb a boost gauge in to check pressure

Quick update, timing good, compression good, boost pressure at pump good, boost pressure at manifold good. Only thing that's bugging me is fuel filter only half full but lift pump seems to be working.. but on another thought I know the injection pump has been played with prior to me fitting the engine so I'm going to swap it out for a known good one.

Lift pump solved the problem ! Thanks for help

Clarky321 said:

Not checked boost pressure at pump, but must be boost pressure at manifold as pipe swells when revving the engine. Not checked the timing as of yet, not got the correct pins at the moment and never really thought to check timing as the engine runs sweet apart from this strange power problem

Click to expand...

This sounds very bad. No pipes should swell at any point. And certainly not when revving. A turbo will not make meaningful boost unless under load, so just revving it will make no boost worth mentioning. I'd suggest you need to look at replacing any pipes that swell, as they could also be collapsing causing a major restriction.