4.2tdi Fuel tank problems

[pwacka8]

Hello All
I have an issue were my 4.2tdi can only run on the first half tank of diesel ,once the needle goes below half way the car cuts out , fill her up with diesel again and shes off.

I had an issue with the car were it wouldnt start ,looking back it all points to the fuel being below half way , because the car ran without issue for the first half tank.

I have been looking into the way the fuel tank is constructed and also the operation of the 2 fuel pumps.

It looks to me like the fuel in the left hand side of the tank is never being used , when i fill up im actually just filling the right hand side which shows on the gauge as full , once all the fuel in the right hand side is used it cuts out.

Why is the fuel from the left side not being used???


There seems to be a bit of confusion on the net over which is the main pump and which is the transfer pump.

It looks like the right hand is the main and the left is the secondary.

Does anyone know the correct operation of these pumps and which does what , i would rather replace one pump than both.

Which one does the transfer of fuel between the tanks??

Is this how it operates??

Thanks in advance

PWACKA8