Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)
Eric Van Kannel

Fuel Line Vent Value/Vent Tube Mystery

Recommended Posts

I have a 2000 Boxster 2.7L with CEL and recurring P0455 error code.  Other symptoms included trouble filling with gas and the howling noise from the filler/right front fender area at shut down.   After some research here I pulled off the wheel and liner to inspect the EVAP system lines and hoses, thinking I would probably need to replace the fuel line vent value.  What I found was the vent tube that runs from the fuel line vent value to the charcoal canister had cracked and broken off where it meets the blue vacuum control valve.  The problem/mystery is that my vent tube is not the same as I see in every parts diagram and help tutorial I can find.  Those diagrams show the vent tube  (part 996-201-255-09) as a direct connection between the fuel line vent value and the bottom of the charcoal canister, running vertically against the canister.  My vent tube runs horizontally along the fuel filler neck to the vacuum valve and then joins another tube in a T connection behind the filler neck.  One end of the T connection runs back up the filler neck to the top of the charcoal canister and the other continues along the back of the filler neck and disappears into the wheel well.  


So, my questions are:

Does anyone know why my car is different?

What is the part number for the vent tube I have in my car?

Is this something I can replace myself?


Thanks in advance.  Any/all help is appreciated.



Share this post

Link to post
Share on other sites
    You can remove these ads by becoming a Contributing Member.


There is a TSB for this problem (TSB 2015 Fuel Tank Hose Modification 3/99).

You should check with your dealer to see if this has been done on your car. If not, they should do it for free.

Share this post

Link to post
Share on other sites

Thanks for the quick reply.  I don't see the STB listed on any of my service records so I'll check with the dealer as you suggested.  Does this TSB change the configuration of the EVAP system hoses and canister to match what I'm seeing in parts diagrams?

Share this post

Link to post
Share on other sites

Probably not - the evap system design changed through the years and some of the early systems are likely not available anymore and must be upgraded when repaired.


The TSB is really about the proper routing of the hoses to minimize vapor trapping and create the proper venting.

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.