Fueling Problem

[petercory]

Purchased an '04 GT3 last week and drove 400 miles to get it home. After 2 hours I stopped for fuel; the nozel was shutting off within a fraction of a second and the fuel was immediately backing up out of the filler neck. Apparently the tank was filled with air (pressure not vacuum) after holding the flap at the top of the neck open for about 5 -10 minutes to let the air escape, I was able to refuel the car. When I stopped again about 5 hours later, I had the same problem. I left the fuel cap on loose overnight and re-fueled about 1 mile from my home the next morning without a problem. Any ideas as to why/how the fuel tank is being pressurised?

[clord]

Hello petercory.... Your problem sounds very much like an issue that quite a few '04 GT3's had during the first year, although, I haven't heard of it happening in the last few years. The plumbing in the fuel tank is quite complex and the filler tube can kink inside causing just the problem you describe. The Mk II GT3 used the C4 unibody for it's additional strength/torsional stiffness. The C4 shell leaves room for the front axel drive that, of course, the GT3 does not have. So, the fuel tank is saddle shaped to clear the front diff that's not there. There is a lift pump in each low point of the tank that pumps into a central gas surge well that has the final pump in it. Suffice it to say, there is a lot of plumbing and wiring in there. I would take to a dealer as the problem is more likely to be remembered by Porsche techs that have been around for a few years. There may well be a TSB on the issue too. Let us know what you find out.

[Loren]

Just to be sure I would also check fuse E6 to see if it is blown.