A6 2002 2.5 TDI - won't start

[A6avantowner]

Please help!!
This morning I broke down on the motorway. Car juddered and I pulled onto the hard shoulder but it wouldn't restart. I was low on diesel, 65 miles left according to dashboard and I've been in that position many times, although this time I was driving up a steep hill. AA added some diesel (not sure how much) and tried the fast start spray, which started the engine briefly. Also, the oil pressure warning light came on briefly at this point.

Ended up getting car recovered back to home.

Just ran VCDS Lite and got these codes:
6 Faults Found:
01318 - Control Module for Injection Pump (J399)
49-10 - No Communications - Intermittent
17978 - Engine Start Blocked by Immobilizer
P1570 - 35-10 - - - Intermittent
17978 - Engine Start Blocked by Immobilizer
P1570 - 35-10 - - - Intermittent
17978 - Engine Start Blocked by Immobilizer
P1570 - 35-10 - - - Intermittent
01268 - Quantity Adjuster (N146)
37-00 - Faulty
17583 - Pre-Injection Turned Off
P1175 - 35-00 - -

I cleared the codes and tried to start the engine but still not starting.

[Crasher]

What can happen is the swirl pot pump in the tank fails (or the relay gets wet) and the injection pump pulls in air which causes the pump to run dry and fail. It has happened to my business partners 2005 AllRoad twice in the last ten years and now he makes sure it has no less than a 1/4 of a tank plus keeping an ear on the relay/pump running; it is a peculiar design having an in tank pump which doesn't actually supply the high pressure pump.

[A6avantowner]

Thanks Crasher for looking at this.
Are there some basic troubleshooting steps to determine that's the failed part?

Like you, I suspected the in tank pump but I'm dreading the thought that it might be the fuel injector pump, although I've had no prior warnings.

Last time I had a problem with not starting, two years ago, it was when I parked on a very steep hill (with low fuel) and the AA man sprayed a bit of easystart into the vent and the high pressure pump seemed to pull the diesel through and clear the air bubbles that you could see in the clear fuel pipe.

[Crasher]

The codes and symptoms suggest the pump has failed, we would start by taking it off and sending it to a Bosch VEP specialist. We use Diesel Fuel Injection Services | P.Atkins | Mansfield partly because they are near where two of my chaps live and they can drop off/pick up. The last one they did for us needed a circuit board and it was over £1k

[A6avantowner]

Yes, it looks like it, the only fault code I have now is:
01268 - Quantity Adjuster (N146)
37-00 - Faulty

I've just looked at ECU Testing web site and they do it for £268 but it's just the circuit board, they don't refurbish the mechanical parts.
I'm assuming that it's not a quick job to remove from the car?

[Crasher]

No, please, not him… notorious in the Notts Derby area.