Gas Cap/pressure in tank problems
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Gas Cap/pressure in tank problems
I have Pressure/Gas Cap problem...My car smells like gas a lot...I can smell it on the back by the tank...The other day right after I turned the car off...I was trying to smell where it was coming from...and I heard a noise from gas cap....like are pressure was too strong and air was escaping through the gas cap....I took it off and all the pressure scaped out
Should I just buying a new gas cap to fix this problem?? if not....What is causing the excess pressure?
I am also having starting problems and I am thinking its linking to a bad gas cap and not enough pressure in tank due to it.
Please help out with any ideas....Buying new gas cap tomorrow
Should I just buying a new gas cap to fix this problem?? if not....What is causing the excess pressure?
I am also having starting problems and I am thinking its linking to a bad gas cap and not enough pressure in tank due to it.
Please help out with any ideas....Buying new gas cap tomorrow
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Re: Gas Cap/pressure in tank problems
will i cant help you out yet. i have the same thing going on with my car. i also have a line that vents the tank and sometimes i drips. so im looking to fix this but if i find anything out i will let you know
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Re: Gas Cap/pressure in tank problems
you have a gas leak, its not your cap.
I run a vented gas cap on purpose.
Never had a problem with it or smelled anything.
gas cap name brand
Clean-Fill
part # CF 701
I run a vented gas cap on purpose.
Never had a problem with it or smelled anything.
gas cap name brand
Clean-Fill
part # CF 701
Last edited by Gumby; 11-21-2010 at 12:59 PM.
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Re: Gas Cap/pressure in tank problems
There's a tank pressure valve up under the hood connected to the charcoal canister. If it's not working correctly, the gas tank can build excess pressure. I had the same thing going on with my 89 305 TBI, the tank still leaked past the cap after I disabled the cap's ratchet with epoxy. After changing the pressure valve with one from the junkyard, problems seem to have gone away.
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Re: Gas Cap/pressure in tank problems
There's a tank pressure valve up under the hood connected to the charcoal canister. If it's not working correctly, the gas tank can build excess pressure. I had the same thing going on with my 89 305 TBI, the tank still leaked past the cap after I disabled the cap's ratchet with epoxy. After changing the pressure valve with one from the junkyard, problems seem to have gone away.
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Re: Gas Cap/pressure in tank problems
It's circled down on the lower left. Not very good, but the best I have without going out to take one. This is when I had the motor out of the 92 V6
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Re: Gas Cap/pressure in tank problems
Thanks again
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Re: Gas Cap/pressure in tank problems
ok om going to apologize for this now. but seeing that we are on the gas pressure.leaking problem. i looked under my car after work today and i have a line comming out from my tank that runs with the rest of the fuel lines. it is about 6" long. where dose this belong to or did the last owner add this for some reason. thanks for the help.
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Re: Gas Cap/pressure in tank problems
IIRC that valve has barbs on the fittings so the rubber tubes don't readily slip off, no clamps that I can remember. On the emissions diagram I found, it's called the tank pressure control valve. I found a replacement in the junkyard and pocketed it while fishing for other stuff. So far I've had no leaks past the gas cap, but I need to put one back on that ratchets to be 100% sure.
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Re: Gas Cap/pressure in tank problems
IIRC that valve has barbs on the fittings so the rubber tubes don't readily slip off, no clamps that I can remember. On the emissions diagram I found, it's called the tank pressure control valve. I found a replacement in the junkyard and pocketed it while fishing for other stuff. So far I've had no leaks past the gas cap, but I need to put one back on that ratchets to be 100% sure.
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Re: Gas Cap/pressure in tank problems
so that valve goes into the rubber hose that just hangs down? can i get one from a part store or not? and if i put one back in will that fix my problem? i now i have a lot of questions but this is my frist 3rd gen and im not the best with the fixxing the fuel issues that im having. thanks
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Re: Gas Cap/pressure in tank problems
tater7765, I don't know about the tube you have hanging from the gas tank. This valve goes under the hood at the charcoal canister.
Last edited by Al Hasse; 03-18-2009 at 11:34 PM.
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Re: Gas Cap/pressure in tank problems
you won't see any drips unless its allot, there is a heat shield pan under your tank that will collet allot of fuel before it spills over, you will still smell it but not see it.
Do your typical drive, then reach under n bend the corer of that pan down.
Do your typical drive, then reach under n bend the corer of that pan down.
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Re: Gas Cap/pressure in tank problems
it is like a small streem for a bit the it is a fast drip. it comes from the tube that runs with the fuel lines, the it stops and i dont know what it goes to.
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