2001 Mustang GT -- Valve Assembly Pressure Regulator Solution Found!

Hello Everyone,

So I finished a 9 month partial restoration of my 2001 GT. Soooo good to have it back on the road now. One of the hurdles I ran into and panicked about was the fuel tank "Valve Assembly Pressure Regulator"... the bigger of the two blue valves that you find on the fuel tank. The exact ford part number is extremely rare if not gone. HOWEVER.... I found the model from a Lincoln is a solution. The ford part number is YW7Z-9B190-AA. That is important, there are similar part numbers that are not correct. I have a photo of the box attached. They are hard to find too, and about $75. I bought mine from AutoNationParts.com, some rather obscure site. NOTE the seal going into the tank is pretty much nonexistent too... so I reused my 23 year old one unfortunately. Someday I might have to do something about that. I am not referring to the "fuel tank vapor valve" found on popular websites like LMR (the smaller of the two blue valves in the tank).

NOTES: They aren't identical in the sealing and seating area. See the side-by-side photos... but they're close. The blue one is OEM, and it got destroyed taking it out of the tank (I painted the tank). The new unit fits a bit loose in the hole in the tank (with seal) included. My solution to this was to take some CNG/house natural gas sealant tape and put a few loops around the sealing area, then I used Permatex "The right stuff" RTV sealant on the flange to seal it to the rubber gasket. I REMOVED and discarded the seals that came with the new unit... no O-Ring installed. I am fully aware these materials are not necessarily gasoline rated, but i figured what the hell. I tried a few other things and FAILED to keep the model in place and sealed. Permatex Permashield #85420 in an orange tube DOES NOT harden and hold the unit in. i also tried Gasoila E-Seal (rated for ethanol), and that did not harden either.

I proceeded to finish hooking up the tank with some basic fuel hose and hose clamps. So far, I have been driving around for about 500 miles (breaking in my new 4.10's ). The fuel tank fills properly, and so far the sealants have held. I do not smell any gasoline vapors, and no check engine lights. If anyone has questions let me know. I attached the photos rather than inserted them.

yeah it seems like a line is plugged, one of the hoses is kinked or squished, or the valve you used has too much spring pressure/broken. Like 89 ripper said, could be plugged in the charcoal canister. If it was filling up properly before you put it in there, maybe try ordering one of the units I mentioned above and putting that in there. Luckily our tanks aren't the hardest to take out.

As a recap, I finally just put the stang away for winter 2 weeks ago but the repairs i mentioned worked fine to this point, no check engine lights, vapor lock, or fumes.