Weird noise coming from around the fuel tank nozzle...

[El Patrick]

This is on a 1997 Boxster (2.5L) 5-speed manual transmission with 33k miles.

After driving the car and then parking it and shutting the car off, I begin to hear a strange noise coming from around the gas tank nozzle and the passenger side front fender well. I'm not even sure how to desctibe the noise, but almost like a droaning/bubbling noise. After minutes of being puzzled I unscrewed the gas tank cap to let the vapors out and the noise stopped... I left it unscrewed for maybe about 1 minute then screwed it back on and the problem was gone.

I'm at a complete loss, but does anybody know what this issue could be? Off the top of my head I thought maybe something with the fuel pump or fuel lines? Maybe a bad charcoal canister?

Thanks for the help!

*Update*

I just took the car for a 15 minute jaunt around the neighborhoods. Got back home, parked it and no sound. I'm wondering if it's only on long drives.

Edited November 6, 2008 by El Patrick

[El Patrick]

65 views and no replies? Surely someone else on this board has had this problem before! :angry: :P :D

[Loren]

TSB 4/97 24 Humming / Vibration Noise from Fuel Return System -- dated 4-29-97.

[El Patrick]

What exactly does that mean? Is that a recall or something? Do you know what the problem is?

[Loren]

This is why people become Contributing Members here - because they have access to Porsche documentation.

From the TSB...

"Concern: At an ambient temperature near 41° F (+5° C) or lower, a humming / vibration noise may be noticeable after cold start for approximately 30 seconds.

Information: This noise is caused by oscillations in the fuel system piping. This noise is mainly noticed in the dashboard area or front luggage compartment. As of February 10, 1997, production and engine number 65V 04654, a modified fuel pressure regulator and fuel return line are installed.

Repairs: In case of a customer complaint, the new fuel pressure regulator and fuel return line can be installed.

Parts: 993 110 199 01 Fuel pressure regulator

996 110 316 07 Fuel return line"

[El Patrick]

Thanks for the help! Too bad there isn't a Porsche dealership in my town.