2004 A3 TDI DSG FUELING PROBLEMS!!

maui_matt

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Hi,

My 2004 MY A3 TDI with DSG is failing to start/fuel.

My fault diagnosis so far is as such.

The lift pump in the tank does not prime when the key is turned in the ignition, have removed the pump and bench tested it with a 12v source and it runs perfectly and also slaved into another car and it functions correctly in there too!!
I can make the car start and run when I apply the 12v source to my pump in my car but if I then remove the 12v source it then runs for several minutes then it will cough splutter and die, i'm guessing the pump runs continuously once the engine is starting? and thus the car then dying is fuel starvation as it has used up the fuel in the filter?

Is there a relay I can check if so what number, location or part number, or is signalled to work just from the ecu?

At a bit of a loss now i'm convinced that its:

A a fuel starvation issue that is causing the non starting

B the lift pump is not being signalled/powered to work by some means.

Many Thanks

Matt
 
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There is a relay in the system somewhere as it went on mine once. I cannot help as to where it is though as i ****** hate electrics and got a mate to sort it for me.
 
Thanks Devonmikeyboy,

Theres only 2 places to look obviously the fuse box in the engine bay and the other being the relay board under the dash in the drivers footwell location,
do you remember which one??

Does anyone have a wiring schematic / diagram?

Thanks again

Matt
 
Sorry forgot to Post;

ENGINE BKD 140 NO MODS
GEARBOX DSG CODE HLE

Many Thanks

Matt
 
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Check the relays under dash on the relay plate that sits above the central electrics module & behind the fusebox, seems to point towards position 2.1 on the plate, it is marked & possibly numbered 395, elsa is kinda vague tbh.
 
Cheers for the Pointer NHN,

Have located 395 Pt# 8Z0951253 and tested it on the bench cover off and it clicks over as it should when powered up with 12v across terminals 1+2 and power goes through both terminals 3-5 and 3-4 when switch, but will test it on another car to ensure it works, bit stuck to try with my car at the mo as the engine is out for some other work but will have it back in soon!!

NHN Any chance you have a wiring/circuit diagram for the fuel pump?

Thanks so far

Matt