twentysevenlitres

If you get yourself to the end of my thread (which you linked to above) you'll find the the cause of all my woes was a split fuel hose on the pump assembly.

In my case this wasn't easy to find, but from a recent thread I read somewhere I'm not the only one to have had this issue.

A split hose will stop the system pressurising and give exactly your symptoms. If the fuel pump was new 2 years ago, I doubt it's faulty.

Prospeeder

Just add a few gallons of gas.I know you jacked the car up but my A8 did the same thing to me. Said 1/3 of a tank and was gurgling, I Added a few gallons then it started. It then worked fine afterwords. But it made me nervous so i removed the pump and replaced that oring on the siphon, and realigned everything and it pulls fuel down to the last bit.

QUA8RO

Great point, Marty. Thanks.

I've got the whole assembly out right now and it will be easy for me to check.

My replacement VDO pump is here and I'm waiting on my bushing kit.

QUA8RO

Thanks, Prospeeder. You may very well be right. At this point, I'd probably rather *not* know if adding a few gallons would fix it.

I did try adding a solid quart and that didn't prime it. Now I've got the whole assembly out and a replacement pump and gasket kit on the way. It has come apart nicely, without any aging plastic breaking on me. So I've got that going for me.

I also picked up a boroscope for assisting on the re-inserting of the assembly into the tank. My kids got a kick out of looking in ears and up noses and into mouths with it. So it was a worthwhile purchase if just for the laughs.

QUA8RO

...and we're back alive.

Gasket set arrived on Thursday, and I was able to pretty easily swap out the pump and reassemble the whole fuel pump assembly. There were a few great tips and reference points from the "George g" video on youtube ( ). If he's here, a big thank you.

I picked up a usb boroscope in the process, and it came in pretty handy getting the assembly aligned with the components in the tank. It wasn't easy to get the boroscope in place, and it wasn't easy to get the fuel pump assembly aligned... but I did. As the FPA sat nicely on its rubber seal, The tip was above the female part. Frustrated, I called it a night and went up to supper. During the meal it occurred to me that the long bolt would probably bring the female part in the tank up to mate with the FPA's male member. So back down to the garage I went and watched the two of them get it on through the borosope. Up, up, up she goes...

Call me a voyeur.

This approach doesn't seem 100% correct to me, but everything seated so nicely. I still have a concern about half-tank issues, but there's a very simple way to find that out. Drive it until we get past the issue... or not.

I had some minor issues with leakage at the fuel pump line connections. While swapping out the crush washers that came with my fuel filter kit for the originals, I took the opportunity to blow through each of the filters, and the old one was much more strenuous than the new one. So, if there's a lesson to be learned, kids, change your filter at least once every 245k miles. It might make a difference.

Thanks for all the help here. I'll post a closure message once I get past (fingers crossed!) the 1/2 tank issue.

twentysevenlitres

Did you check the in-tank seat for the pump assembly was hooked over the fuel inlet tube (top center internal "roof" of tank) before inserting the FPA?
That would be the cause of many NQR matings in my estimation, as it caused me about 4 hours grief!

Also, the FPA corkscrews into the tank quite nicely. If you get it right, it doesn't fight you at all and lands square on the internal seat (once I learned this, I got it in and out 2 or 3 times without hassle). From (petrol fumed) memory, at corkscrews through just over 180° going in or out but can't remember in which direction it's clockwise!

nyrobbie77

I'll need to look at this as well. I was having dying out problems with low tank. I thought it'd be the fuel pump and when I took it apart I found that it was the original fuel pump. Testing the pump on the bench showed it still worked. I dissected the pump and found that the armature was worn down like seen in most pump failures.

I got the new pump installed and am still having low tank issues. I'm thinking I may have a bad line as well. I'm fairly certain everything is lined up correctly, so this would explain the low tank issues.

Guess I'll have to get the boroscope back out and inspect.