2.5 TDI Starting Problem

[Soldiurblu]

Firstly I would like to say that I really hope I can be helped here, I am starting to lose faith in my A4.

2 weeks ago my car refused to start, it was blatantly a fuel supply issue, I called out ADAC ( German version of the AA) who got the car running and told me it was the pump in the tank, Now I checked the pump and it is working as it should, i.e. supplying the baffle chamber as it should, I know this pump does not supply the fuel lines to the engine. I have checked all fuel lines for leaks, none. I have changed the filter and the non return check valve on top of the filter.

Basically, as far as I can check, the system is sealed.

The Fault

Every morning when go to start the car it will fire for about 2 seconds and then die, it then takes a lot of cranking before eventually fuel is received by the injection pump and she fires up and runs, with no problem. It seems to me as though it is definitely air in the system, I just don't know where. Its almost as though the fuel is running back to the tank overnight leaving a massive air pocket for me to clear the following day.



Has anyone had this before or know where I can go from here.

Any help would be greatly appreciated

[Soldiurblu]

Further to above, I forgot to mention that the engine code is AKN.

Cheers

[PaulF2.5TDi]

Try checking the return lines at the injectors.

If they are not sealed, the fuel can drain back to the tank slowly overnight and give you these symptoms.

[Soldiurblu]

Many thanks PaulF2.5TDi, I will get onto this straight away and let you know how I get on.

The problem I have got is that I have to wait until tomorrow morning t know if this is the cause.

[ametlib]

Hi,if the immo light in the dash is not flashing, this is definitly looking like air in the fuel lines yes.
If the return lines turn out ok, there is an o-ring in the pump that is known to become hard and let in air.
Its placed in the pumps left side in the front and is on the big allen key screw.

BTW you have the very best forum in your home country ( Dieselscrauber.de) so rather amusing you came to us amateurs;)

[Soldiurblu]

Thanks Ametlib, I will keep the O-ring in mind, might just check it tomorrow while I'm doing the hoses.

BTW, I'm British, ad so as good as my spoken German is, I still have difficulty in reading and writing it, thanks for the tip though, if the afore mentioned cures do not work I will get one of my German colleagues onto it for me.