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Discussion Starter #1
this part of the inspection has a two part test
one is the gas cap itself (which passed)
the other is pressure in the tank (which it failed)

question is how can i possibly repair this.
ive read up on it and i need a source of only 12 psi. i have a compressor but i cant stop it at 12. and i dont trust a regulator enough to stop it for me.

and even if i did get it pressurized how would i find a leak?

is this something i should just goto a mechanic with?


thx
 

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wish I could help about testing, never heard of an inspection like that, how'd the inspector do it? I will say that a leak could come from a few spots though, look at the grommet that feeds the fuel pipe filler neck to the tank, it usually gets dry rotted, out of 6 of my daytona's they all were bad, you can still get this from the dealer anywhere from $10-22.

the other three places would be the sending unit or fuel pump o-rings and the breather on top of the tank, I believe it runs to the engine bay by the right front strut mount metal pipe. It will have a vacuum line running to it from the charcoal canister located just in front of the coil.
 

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These are leak places, but there is also the charcoal canister and the rubber hoses that connect to it. Yes, a low source of air pressure, listening for a hiss, and if that doesn't work, spray bottle of your favorite 409 or window cleaner will work. You need up to 12psi (as in not to exceed), so, a large balloon and a string tied around the end on one of the hoses from the charcoal canister? I say start with the condition of the hoses on the canister first.
 

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Discussion Starter #4
i diddnt know we had charcoal canisters on these old things. what does it look like

when the guy did the test he clamped down some hose near the coil then he connected some special gas cap with an air hose and pumed it up.

however the computer detected that there was a decrease in the pressure so it failed.

ill crawl under and check my gaskets and see if any rot has occurred.
 

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Make sure the metal vent line from tank to canister hasn't rotted, either. These cars are of an age where that can happen, too.
 

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What vehicle are you talking about? Charcoal canisters have been around since the very early 70s. At the same time, the older cars, like my 68 Charger, the vent tube goes up into the C pillar and makes a hook near the top and then comes down to the frame rail and just sits in there, so it is open to the atmosphere. When they get plugged, they tend to vapor lock the gas tank and starve the engine of fuel, so you have to pop the gas cap, so go figure. The charcoal canisters are usually in the passenger side corner of the engine compartment behind the headlight area, big black plastic container with three or so rubber hoses coming off it, if it is missing, that's where the leak is.
 

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Discussion Starter #7
well ok i found the problem which happened to be the hose that goes from the tank to the canister. replaced the tube and ran it back thru inspection passed titled and tagged.

now the county cant nag me about having it
 
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