Fuel Tank Won't Take Fuel

[Juliof16c]

Box 2003 S. Fuel tank won't fill. Read other posts. New gas cap, changed pressure relief valve on filler neck. There is a 'click' with the top flap pushed in. E6 fuze ok. Checked and replaced. With tube from relief valve to carbon canister disattached the tank fills. Reattach it and won't fill again. Took canister out and looked ok. Not falling apart, no pieces floating around. Took to dealer and they poked around and didn't find anything but did say he wired up the wires that are mentioned in TSB #13 and he said it filled up. I tried it four times at different locations and times and failed every time. Tried to find the tank relief valve but couldn't find it. It is sometimes hesitating, like a miss, but usually runs fine. Any comments? Thank you in advance. jp

[Dmitry at Pelican Parts]

Hello and welcome to the forum! Take a look at the link below (it's also applicable to your model), did you check the fuel line vent valve?

Replacing Your 996 Fuel Line Vent Valve / Bleeder Valve - Porsche 911 Carrera & 986 Boxster - Porsche 996 Carrera (1998-2005) - Pelican Parts Technical Article

[Juliof16c]

I've changed the vent valve and still won't fill. It will fill when the tube from the valve to the carbon canister is disconnected. I'm looking for the tank vent relief valve some where in the system. There is a part but no picture available. The parts drawings are so poor that it is hard to track down where things go. I"m still trying to figure out what the magnetic Reed valve is for that is beneath the relief valve on the filler tube. Still not working. It is starting to run with an occasional hesitation like a miss. No warnings on the on board computer. Thanks for any info. jp

[Juliof16c]

Driving today the car started running rough, hesitating during acceleration, and even died at a red light once. Afraid to drive it to the dealer now. Maybe will have it towed. Is this an indication of the carbon canister going bad?

[Juliof16c]

Update: Both the fans failed on the way home. That is why the a/c quit and engine temp started to climb. Fuel tank has been checked for over a month. Every thing I've read here has been tried to no avail. Porsche has been contacted by the dealer and those suggestions, that I don't know, have been followed to no avail. The dealer is taking videos of something and sending that to Porsche today. May have a response tomorrow. I have changed the fuel filler cap, the relief valve on the filler tube in right wheel well. Checked air flow through the tubes I could get at including the charcoal canister. What did work for filling the tank was disconnect the relief valve from the charcoal canister and go fill up. Worked but I got a Check Eng light. And that reset and switched the relief valves and hooked up the tubing again. No go on the fuel tank. I have not tried the previous but told the dealer investigating the sitch of that event. He has not told me if he reattempted it cuz he's doing the Porsche suggestions now. We'll see.