2.0 TDI no start, audi a6

martini667 · Post by **martini667** » Sat Jun 26, 2021 4:08 pm

Hello. I hope there is someone who can help me. I have an audi a6 2.0 common rail no starter. I start from the beginning with the issue. I changed the fuel filter and didn't prime the system and high pressure pump ran dry. Managed to start the engine after a few tries but knocking sound occured from fuel metering valve when revving the engine. I removed/ cleaned the valve and after this car wont fire up anymore. Fuel pressure low. Tried another valve, nothing. Ok, then i thought that maybe i messed up the high pressure pump and it sent metal pieces to injectors. Ordered new pump, 4 injectors and rail with sensors. Coded new injectors. Installed them with new high pressure pump and rail. Primed system like 8 times before starting, still same. No start and low fuel pressure(8000-9500 kpa). Tried to start with starting fluid, nothing. In tank pump and aux pump give 3,8 bar to high pressure pump, is it enough? Does fuel metering valve and fuel pressure regulator need to be adapted to ecu when changed? Im totally lost here..

Technician · Post by **Technician** » Mon Jun 28, 2021 6:33 pm

Can you read fault codes and live data? Fuel rail pressure via scanner?

KimAndersen · Post by **KimAndersen** » Mon Jun 28, 2021 9:01 pm

There is of course the possibility that when replacing the high pressure pump, that the timing belt is not correctly fitted according to technical data.

And here I am thinking of using the correct locking tool for the crankshaft and camshaft - it was worth checking again.

Regards
Kim

picowight · Post by **picowight** » Sun Jul 11, 2021 3:10 pm

Tried to start with starting fluid, nothing.

So you don't have a fuel problem.
You likely have a timing problem if you just took the belt off.
Previously you may have had a power supply to metering valve issue - depending on if it is Normally open or closed. -n This may still exist once you fix the timing.

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