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problem filliing gas tank, pump keeps shutting off

Every time we try to fill the tank, the pump shuts off every few seconds, as though the tank is full. Our mechanic replaced the refueling vapor valve ($400 with labor) which did not fix the problem. Ideas?


  • edited May 2010
    Now have him investigate a stuck "Anti-spill roll-over check valve". Also, use the search feature at the top of this board , enter "slow fill" to read many similar threads..
  • edited May 2010
    Any driver in the habit if topping off the tank after the first shut off?
  • edited May 2010
    yes! I've read that it can cause problems. so now what?
  • edited May 2010
    I suggest heading to a import mechanic and asking them to check/replace your check valve. Commonly, this needs to be replaced due to topping off your fuel, or a fuel cap not being tight/being too tight. Good luck!
  • edited May 2010
    Thanks for the suggestions. I'm curious about a couple of things, though. Do we need to go specifically to an import mechanic? The guy who replaced the "refueling vapor valve" charged me plenty, but has said he'll continue to try to fix it without charging again... However, I think he is out of ideas! Is this valve that he replaced different than the "check valve that has been mentioned twice in this thread?
  • edited May 2010
    Yes, the anti-rollover spill valve is different. If your car happened to flip over this would keep the gasoline from spilling out the fill spout.

    The vapor valve is what allows gasoline vapors to escape the tank. These then run through vacuum hoses to someplace under the hood where they are fed into the engine to be burned. The theory would be that something keeps the vapors from escaping and the pressure shuts off the fuel dispenser. Its not really possible to give that mechanic more ideas beyond that because we don't know what was already checked. The question would be whether or not the mechanic check out any other parts of the evaporation system.

    I think the rollover valve is a more likely problem.
  • edited May 2010
    Sometimes you can dislodge the stuck valve (a cork ball) by slipping a flexible object down the filler neck..One of those bicycle fiberglass flag masts works good or a small, stiff, plastic tube or rod..

    When you over-fill the tank, this ball floats up and blocks further fueling. But if you persist and continue over-filling the tank, the ball stays submerged in gasoline, swells up, and never returns to the "open" position. Once you dislodge it (or remove it) your problem will go away...It is located in the filler pipe right next to the gas tank..

    Don't pay mechanics $400 to fix a problem unless they fix the problem...
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