Dodgy fuel gauge Fault code 00771, unable to remove locking ring on pump

[eddiemacthedog]

Hi people.

I'm having issues with my fuel gauge on my A6 C6 2.7tdi Quattro going to zero now and then and fuel showing 0 miles when plenty left in the tank. Plugged in my diagnostic and get the fault code 00771.IMG_3668.jpg

Any ideas, i was thinking a dodgy fuel sensor but thought id take the pump out to have a look but wow i cant shift the white locking ring, been at it with a hammer and screwdriver but refuses to move unless im missing something. Here is a pic of the pump in situ.

IMG_3712.jpg


Any help greatly appreciated. Was going to get a sensor from ebay but have read about broken wires etc but cant get the bloody thing off!!!

[jrenoc1]

H,
I had this it was the connection in the fuel tank between the two sender units, I disconnected it and cleaned.

Too remove the outer ring you need to tap alternative sides as per the photo, gently or you will break it. Make sure you’ve got as little fuel as possible in the tank.

I made a mark on the sender, outer ring and the paint work as a reference.

When refitting push the sender into position and tighten up by hand the outer ring then again tap alternate sides till tight.

This is where the marks you made earlier will help.

F3715D71-C16C-43B4-83AC-362FE22FE8B8.jpg

[eddiemacthedog]

Thanks ever so much for your reply, What did you use to clean the connections may i ask, I've ordered up a tool to get the locking ring off so hopefully have it in a few days. I was wondering if it may be the connection on the top as pictured as I've took it off and gave it a blow and a clean etc and the gauge works again for a few days then mucks up again but working at the moment.

Whats the best method for cleaning them?

cheers

[jrenoc1]

No worries, I cleaned the connector with some brake cleaner on a rag. Even now I can get a random day when it stops working then it’s fine again for 6 months even though I’ve not touched it.