Diesel fuel problems....
 

Hi all, had a new fuel tank pump fitted during week, which has turned out to be a bit 'iffy'.... i.e not always working! Bigger problem though is that when pumps are turned off, all fuel drains back into the fuel tank, making starting a nightmare, had to clear air from injectors to get it started just now.
Does anyone know why fuel is draining back into tank... you can hear it rushing back as soon as engine turned off, I'm sure the whole fuel system shouldn't empty??
Any help pointers / advice... ZT diesel, 2003, twin pump.
Both pumps working at present, just the lack of fuel once you turn off engine... :-(

Not much help, however....

The only way it can drain back down, is if there is air getting in at the high point of the fuel system. If air can get in, fuel should be able to get out - which would be obvious, but you are not mentioning any leaks. Have you had the engine cover off and checked?

My first step would be to check all fuel pipes and connectors and most certainly I'd look again at the fuel pump to see if it's been fitted correctly and all connectors fitted correctly.

Hi, yes, cover was off to get car started earlier today via assistance... lots of air in system, had to remove 2 injectors and wait for fuel to get through with pumps running before I could get car going.... there s fuel there, just not after ignition is switched off. No apparent leaks in engine bay or under car....

Hi, anyone have a decent schematic of the tank system? Best I have is the Rimmer Bros parts diagram, nothing in Haynes... no idea if the whole assembly was put back together correctly, although fault code for pump had cleared and car did do 70 - 80 miles on 2 trips before problem started...

I think t-cut made a diagram, but it was mostly intended to explain how the fuel system worked.

Well finally got fixed today..... the new In tank fuel pump I purchased kept cutting out, not least on the way home from work tonight... so this was replaced by the supplier. In for a penny, I also bought and replaced the under bonnet pump when I got home, as both parts arrived today. When changing the in tank pump, I found the garage, who charged me £140 in labour, had not fitted the fuel pump filter, supplied with the pump, and had also not relocated the fuel intake plastic unit correctly into it's position. Anyhow, with all jobs done in one hit, we look to be back on track and starting without hitch.... Wish I hadn't bothered with the garage though.... it was the fault code that threw me, P1260, which was not vehicle immobilised, but a low fuel pressure indication. Thanks as always to everyone who helped, especially Phil T4, who gave me the correct fault code explanation, albeit after I had the car towed away... Bu""er!!