could there still be air in the fuel pump even after sucking over a litre out

Boxa wrote:

its sucking it through instead of pushing it through would it make a difference

Boxa wrote:

could there still be air in the fuel pump even after sucking over a litre out

I connected a pump to the green fuel return pipe on top of filter and sucked fuel through

that should work Jules

unfortunately I still have low fuel rail pressure so im stumped

Are you certain the HP pump is actually being driven ? IIRC the bit that connects to the HP pump is seperate to the actual camsahft. THough Id need to check on that . Jules

well ive just rebuilt it all so I assume so ill probably take the pump off tomorrow just to check everything is ok

thing is though you can see pressure rise on scanner when turning it over ? but ill remove it and have a look just to make sure its all intact

Ive just remembered vaguely reading on here that the HP pump needs an electrical signal to shut a bleed off valve. Im sure it was on the forum somewhere. Without the signal the HP cant muster any HP.

Would that be the next thing to check rather than further dismantling. Jules

that's very interesting if only I could find the link

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Under TD4 Electronic engine controls it says the HP pump has a " volume control valve"
Could that be the problem ?? Jules

I was looking at that earlier today thinking exactly the same thing but its still pump off to have a look

Boxa wrote:

that's very interesting if only I could find the link

I agree but im a new member and he might not appreciate me asking for advice so soon