I am not easy to get my feathers ruffled... but your "factory" drawing are worse
than BAVARIAN... Took me quite a
while to determine your "GROUND
" is the "br
wire emerging from your PUMP... You have effectively
eliminated all other possibilities...
I don't understand why... but it APPEARS to return
to the driver area (no... not confusing it with fuel gauge)...
LOTS of opportunities
for damage, corrosion or dirty
Since you were already DARING ENOUGH
to the pump (I would NOT
testing the GROUND
might reveal your next quest.
Personally... (for wiring diagrams (factory is detached))
I would beg, borrow or BUY
book... or use a decent mechanics SHOP
Amazon com Bentley Paper Repair Manual VW Jetta Golf GTI A4 Automotive
I think you are almost there... (I would NOT
Temporarily supply a local GROUND
for your pump ...
(I simply don't do ELECTRICS at the FUEL tank - EVER).
I am attaching the "Do it Right" recommendations
from Delphi... (please read)
More Information for DELPHI FE0723
As you are already into the tank... you can likely SEE
any issues with the fuel... However having BEEN THERE...
I would STILL
take the additional step of evacuating and
cleaning the tank...
Read & heed the above "Do it Right" ... I will
only add that cleaning injectors with Berryman
Choke & Carb cleaner has helped wash away the years of poor quality fuel. Amazon com Berryman 0117 12 Chemtool Carburetor Choke and Throttle Body...
Hope this helps
Carnac the Magnificent