fuel tank vent / breather question

Posted by 1Gina2G, Jan 9, 2012
Newbie Forum - Beginner DSM modification questions and discussions. Common, repetitive, and general discussions will get dumped here from other tech forums. Unless you're a Probationary member you shouldn't post threads here.

  1. 1Gina2G

    1Gina2G Proven Member

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    Beaufort, South_Carolina
    The charcoal / emissions canister has been deleted from my car, but the hardline that used to go to it, which is the fuel tank vent, still has this small plastic piece hose clamped to the tip of the hardline, I don't think it's a breather, but I'm not sure what it is, it looks like what used to be there for the canister, right next to the hardline for the fuel filter.

    Should I take it off to vent better? Still not sure what a breather is or if I can buy one at a car parts store?

    I'll post a pic on here later today to show the weird plastic piece I'm talking about.
    #1
  2. Swarley815

    Swarley815 Proven Member

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    A "breather" is a small filter that you can get at just about any parts store. From what i have read you should def vent your fuel tank just not in the engine bay for safety reasons. Also there is no real gain to getting rid of the charcoal canister so it might be easier to just replace it with one from a donor car.
    #2
  3. 9!'clipseDOHC

    9!'clipseDOHC Moderator

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    El Paso, Texas
    If the 2g setup is the same as the 1g, then that hard plastic piece is a check valve for the vent/emissions system. No one has come up with a perfect system for the fuel tank vent line with a removed charcoal canister/vacuum source. Most people, myself included, just route that line out of the engine bay and leave it at that.
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  4. 1Gina2G

    1Gina2G Proven Member

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    Beaufort, South_Carolina
    This is also something I was wondering about, so some people just bend the hardline back, under the car? Just to get it out of the engine bay? Doesn't seem like it would really get in the way of anything, just seems the canister just gets in the way so I'd rather just leave it out.

    Does anybody know if I need a different intake pipe if you don't have a canister?? Since a tube leads from the canister to the turbo's intake pipe??
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  5. ed1380

    ed1380 Proven Member

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    ATL, Georgia
    Just plug intake pipe when the charcoal canister connected.
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  6. 9!'clipseDOHC

    9!'clipseDOHC Moderator

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    On mine I just added another vacuum line to route the vent line out by the passenger wheel. It's just to keep any fumes from the tank from filling up the engine bay or making their way into the cab. As stated just cap that line on your intake pipe.
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  7. 1Gina2G

    1Gina2G Proven Member

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    Beaufort, South_Carolina
    I think you meant to say, with the canistaer disconnected correct?

    Should rubber hose caps be fine for the intake pipe?
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  8. 952g63t

    952g63t Proven Member

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    Not originally, West_Virginia
    Sorry to dredge up an old thread, but I've also been debating on what to do with my breather line.

    Can you route the breather hose (after the check valve) to your intake or intake manifold?
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  9. black_gst

    black_gst Freelancer

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    IE, California
    im not sure what everyone does now, but i just have a random PVC check valve that allows air in but not out of that vent line and i never smell fuel
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  10. Spoolin98

    Spoolin98 Proven Member

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    Isnt the purpose of the vent line to allow air out?
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  11. gophishy10

    gophishy10 Proven Member

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    That's what I thought too. I think he has his check valve backwards.
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  12. Joethefallen23

    Joethefallen23 Proven Member

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    The purpose is to prevent excess pressure in the tank from the buildup of vapors. Have a check valve only allow air in is simply no better than just plugging the hard line. I routed mine into my passenger side wheel well. Zip tied it to my trans cooler with a little fuel filter on the end to keep dust out.
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  13. arbiter

    arbiter Proven Member

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    Irun, Europe
    In europe car (Apart from VW/AUDI/SEAT) it is usual to find a Pitsburg valve connected to wot pedal, to let the intake suck the vapour from the tank.

    It is very common to find this on Opel cars, wich is a brand of the GM group.
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