Reviving this thread because it had a lot of good info, and I have a related question.

Is there any other component or reason that would prevent the fuel pump from running when the door is opened?

I have a 2004 CTT, and recently filled it full with fuel (91 octane is the highest available in CO).
Drove it home, it was fine, next day it started fine but then stumbled and bucked once I left the neighborhood. I returned right away, and at times is was barely running, other times it was fine.
It sat for about 2 weeks, Moved it into the driveway and it barely started (low battery). Charged the battery over 24hrs. Battery is one month old.
Yesterday I went to work on it thinking coils.
Tried to move it a few inches in the garage, started fine then died. Started again and then died a few seconds later.
I check fuel pressure, a small amount of fuel sprayed out f the Schrader valve n the fuel rail, but the gauge read 0psi. Tried opening the door, and no running pump. The door switch works, and the lights turn on, I can also hear another pump run under hood. But no fuel pressure.
I checked the fuses for the 2 pumps, both fine. I swapped the fuel pump relays for 2 identical ones, and no fuel pump sound when opening the door, no fuel pressure.
I didn't do the test mentioned above to remove the relay/fuse for the primary pump to see if the secondary pump runs fine.

I did drain 10gallons from the tank, using a Harbor Freight hand pump, and was able to remove both pumps, the pressure regulator, and the filter. The filter drained out some very black slimy stuff.
I have not tested the pumps with 12v yet.

Is there any other roll over switch or ECU issue or door switch problem that could prevent the fuel pumps from running? Everything else works and there are NO faults with Durametric!

 

Vulcan - I experienced the similar thing - was in 06 S driving to Breckenridge from Chicago, was running close to empty - pullup over in a middle of nowhere east of Denver - the place only had 89 gas, I put few gallons, then I think I filled up in Indian Springs, I spend few days skiing in brek (car is parked at condo) then I tried to start it and it wouldn't - it's cranking but not starting, took a couple minutes to fire up, I would crank, freak out for a minute, crank again, after 4-5 tries it started. I drove to the grocery store, left it running in the parking lot, got groceries, drove to gas station by Breck Brewery filled up the full tank without turning off the engine. Next time it started fine and been starting fine ever since. I blamed the bad gas\altitude\freeze&thaw for the problem.

Did you try putting good gas in it ?
My friend once was filled with something so bad at Citgo - gas station ended up paying 2k$ for repairs, and many people were affected.

I think fuel pump wouldn't run if there is pressure already in the system or maybe there is a timer, like if you open the door 10 times - it will not run all 10

 

The tank was totally full, so I didn't try other gas before removing the fuel pumps. I don't think bad gas would prevent the pumps from running though. There would be fuel pressure.
Saturday when I was working on the car it was almost 60deg, so there wouldn't have been any frozen water in the system at that point.

 

Tested the fuel pumps electrically last night.
The primary pump (left pump behind driver) was totally dead
The secondary pump spins with 12V, but I'll replace that as well.

I should have tested the secondary pump while it was still in the car, by removing the primary pump relay before opening up the tanks, but it was easy to test with a battery.

Anyone have any recommendations for where to buy pumps, or where not to (don't work, or don't last)?
Anyone confirm whether the Touareg pumps are the same, or not?