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gas tank pressure

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Old 03-01-2006, 04:30 PM
  #1  
tokinGLX
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Default gas tank pressure

ive noticed the past couple times ive filled up my gas tank that when i open the cap, it vents out for a couple seconds. i think i read that there are venilated gas caps...¿ is this something any auto parts store would have or eb able to order, or is there any other fix to this¿

i didnt notice it right away, but it was probably just because i wasnt really paying attention, but im pretty sure it would have started after installing an electric fule pump
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Old 03-01-2006, 07:29 PM
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rmodel65
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Default RE: gas tank pressure

supposed to do this, brand new cars pressurize the fuel tank as part of there emission controls thats why u arent supposed to top off newer cars there is supposed to be air space for the gas to expand when it gets hot!
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Old 03-01-2006, 07:41 PM
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tokinGLX
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Default RE: gas tank pressure

but my car is far from new, its an 83, and it has never done this in the past
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Old 03-01-2006, 07:44 PM
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rmodel65
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Default RE: gas tank pressure

its the light end of the gas they seperate when the gas heats up when these escape u lose octane u should always tighten until ur gas cap clicks the dealerships charge like 50 dollars on a new car to turn the check eng light off!
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Old 03-01-2006, 07:50 PM
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lookinforastang
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Default RE: gas tank pressure

huh? how does it lose octane?

it's just compression that builds up over time
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Old 03-02-2006, 01:10 AM
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tinman
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Default RE: gas tank pressure

I think an '83 car will still use a vent on the tank.
Could be yours is plugged with ka-ka of some sort.....
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Old 03-02-2006, 01:26 AM
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tokinGLX
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Default RE: gas tank pressure

is it possible to unclog it, or do i have to get a new tank¿
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Old 03-02-2006, 09:36 AM
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stanglx2002
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Default RE: gas tank pressure

make sure that the secondary fuel line isnt capped off that would pressureize the tank. They run along the passenger side of the car both fuel lines. one line goes to the fuel rails and the other is surpose to go to a carcoal canister. About half way down the passenger side the line should turn from metal to plastic. The plastic line goes to the canister. if the plastic line isnt there and the metal line is capped off you need to take the cap off and then your tank wont pressureize anymore
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Old 03-02-2006, 01:07 PM
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tokinGLX
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Default RE: gas tank pressure

keep in mind, that i do not have fuel rails. i dont believe i have a charcoal canister either. about a month ago i had to reroute the fuel lines to move them away from the headers, bot lines go into the fuel pump.
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Old 03-02-2006, 01:18 PM
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angcobra
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Default RE: gas tank pressure


ORIGINAL: tokinGLX

keep in mind, that i do not have fuel rails. i dont believe i have a charcoal canister either. about a month ago i had to reroute the fuel lines to move them away from the headers, bot lines go into the fuel pump.
Did you change to a different type of fuel pump or just a direct replacement?
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