Evap problems gas pump shuts off ?

1994 CHEVROLET CAVALIER
100,000 MILES • 4 CYL
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GLEN S
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Ok here it is the gas pump shuts off after a half gallon is put in then the car breaks down and won't start ok u know part to start I went threw the check list purge vaulce clicks when giving power ok weird part to me is the vacuum lines are unhooked from the canister and the car runs a bit better even runs good when the EGR is in hooked . Idk anyway I blew the lines out when I was blowing the vent line out it blew gas out of the inlet where I put gas in ok so I went back there and tried to blow through there and it blew gas back at me .I removed the tank and checked every thing seemed good I even removed the pump which is new it's good .Iv done alot for no good I need some help
Mar 24, 2026 at 12:34 AM
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STRAILER
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Okay, lets check for fuel at the purge valve. Remove the vacuum line and check for fuel, also once the valve is removed you should no be able to blow through it. Also, check the charcoal canister, is it heavy with fuel? Do you see fuel in the lines to the canister? Many fill problems are caused by the small vent tube alongside the filler neck being blocked or kinked. If that small vent path cannot move vapor out while filling, the gas nozzle will keep shutting off. Here is the location of the purge valve. Check out the images (below). Please upload an image or a short video in your response, so I can see what's going on.
Mar 25, 2026 at 11:47 AM