Lack of power in 4th and 5th gear.

This seems to be an intermittent problem although it's more often than not and it's driving me mental as it makes for a horrible drive. Around town driving and on generally flat roads it's mostly ok and has ok power in lower gears. When I go into the motorway or any national speed limit roads with hills though it basically completely loses all power. Today I joined the motorway and even when up to speed at about 65 as soon as I hit even a slight incline it basically dropped down to 45mph before I had to drop to 4th and even then it's a struggle to get it back up to speed. On todays drive however it then started randomly driving properly great and was brilliant for the rest of the drive up until the last 40 minutes when it completely lost any power again and I had to leave the motorway. I've replaced the fuel filter 3 times, fitted a new lift pump, ran a cleaner through it and still it's no better. Anyone any other ideas as I don't know what's going on? Literally the only thing I can think of is that I changed a pipe on the turbo that operates the wastegate as the previous one was worn through. I'm sure since then it's had these power issues but that can't be the problem. Hose I replaced is circled in the picture.

96 plate 300tdi 110

Sometimes the pipe going from the turbo to the steel pipe leading towards the intercooler delaminates.
The 90 degree one ... PNH1020

You can normally see it if it has, as a lump on the inside wall, you can't see it from the outside.

miktdish said:

Sometimes the pipe going from the turbo to the steel pipe leading towards the intercooler delaminates.
The 90 degree one ... PNH1020

You can normally see it if it has, as a lump on the inside wall, you can't see it from the outside.

Click to expand...

Ill need to start having a look around all the hoses and pipes as I can't think of anything else it can be

Is the waste gate pipe been restricted by the vacuum pressure(collapsing pipe)& not allowing full movement of the waste gate?

Blocked fuel pipe/pick up?
Could also run but would not pull top gears. Fitted an override pump(was on racer) & this would pull more fuel than the standard lift pump. Piece of wood in pipe had gone up it,fitted a series gauze on the pipe after

Hicap phill said:

Is the waste gate pipe been restricted by the vacuum pressure(collapsing pipe)& not allowing full movement of the waste gate?

Click to expand...

As far as I'm led to believe it's positive pressure so this shouldn't be the case. Only other things I could think of relating to this were that the wastegate is seized from being parked up and not opening fully, or the pipe I fitted is ballooning under pressure and not allowing the wastegate to fully open. This should overboost the turbo though

Hicap phill said:

Blocked fuel pipe/pick up?
Could also run but would not pull top gears. Fitted an override pump(was on racer) & this would pull more fuel than the standard lift pump. Piece of wood in pipe had gone up it,fitted a series gauze on the pipe after

Click to expand...

The fuel pick up was replaced during the chassis swap, id had this low power issue in the short time I was driving it before that.

+1 on the turbo hoses, can be a leak, it disconnected or sinply desintegrated. As she did have full power before loosing it again, maybe a leak or a loose hose. Had that on one of our other cars, also a turbo diesel engine.

hef19898 said:

+1 on the turbo hoses, can be a leak, it disconnected or sinply desintegrated. As she did have full power before loosing it again, maybe a leak or a loose hose. Had that on one of our other cars, also a turbo diesel engine.

Click to expand...

I'll have a look around today and check all of them. I think it is a turbo/boost issue rather than a fuel one

Suspect this may be my issue then. All other turbo hoses fine apart from this, the boost control pipe from injection pump to turbo has at least 1 pinhole worn through. Going to get a new one today and see if that sorts it