What's wrong now.

As usual we have Dora the disco playing up. Climbing a hill with the foot to the pedal the engine is pulling then not then pulling then not it seems to be fighting with itself slightly. On the straight etc it's fine.

Popped the bonnet reved it up and noticed after reving it the engine misfired I watched it go lumpy and then carry on.

After reving it the engine cut out and wouldn't start. Left it a minute and got it started again.

It's had a full service recently including all filters , it's had new turbo to intercooler pipe new exhaust and inlet manifold gasket. Downpipe and De cat and the egr is blanked. Had all new injectors 9 months ago. Sedimenter bypassed.

What's wrong :-(

Not enough fuel flow? Fuel pump perhaps? Or maybe lift pump? Just a couple of guesses from a non D1 owner. Hope it helps!

lift pump possibly, but there is a small gauze on the bottom inlet union that can block with crap especially if the sedimenter has been by-passed, or it just plain failed.

doesn't sound like air entering the system from your description.

I was worried that the manifold gasket I had done wasn't done properly but I can't see a black soot around it it seems clean and that air was getting in. Where is the inlet union?

Fuel lift pump looks new. Don't know anything about fuel pump. Is there anyway to find out if it's either?

Put a piece of clear fuel line in - you'll see if there is any air getting in, which will check that bit of the fuel line out. If you see bubbles you have a problem somewhere !

Without looking I presume the pipe is around 8mm? I'll order some clear to go from the fuel filter to the lift pump to check for air. Whilst I'm at It as well I'll remove the sender cover and check for leaks and corrosion. Is it definitely air and fuel related?

brettguise said:

I was worried that the manifold gasket I had done wasn't done properly but I can't see a black soot around it it seems clean and that air was getting in. Where is the inlet union?

Fuel lift pump looks new. Don't know anything about fuel pump. Is there anyway to find out if it's either?

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Hi BG, there is only one fuel pump on the TDi 300 and it's called a lift pump - driven by a cam on the drivers side of the engine.

For the price of them I would just replace this, they are cheap and it's a very easy job to do.

ERR5057 | Fuel lift pump - mechanical - 300TDI


Dave

brettguise said:

Without looking I presume the pipe is around 8mm? I'll order some clear to go from the fuel filter to the lift pump to check for air. Whilst I'm at It as well I'll remove the sender cover and check for leaks and corrosion. Is it definitely air and fuel related?

Click to expand...

Sounds like its sucking in air to me. Mine did something similar. I put new fuel sender on it and bypassed the sedimenter and it sorted it.

Only a little thing bit make sure the fuel filter is sealed properly might need the seal wetting with a drop of diesel or nipping up a bit