Fuel Tank Pressure Discharge??

[dls322]

Hi,
I had a question about my fuel tank. When uncapping the tank to refill, there is a ton of pressure in the tank. I get a heavy hissing sound as the vapor vents. Depending on how quickly i open the cap, it could take a few sceonds to full empty. Granted this kinda sounds cool at gas stations but is this a problem?? I've never had a car that had this issue. Thanks in advance everyone!!

 

[stang22]

Do you have the charcoal canister hooked up? That vents pressure from the tank to the intake so that does not happen.

Tim

 

[dls322]

The pulley goes to the pump but i'm not sure if it is actually working. I was looking into an a/c delete kit and read your post on leaving the smog pump. Is this built up pressure bad? Am i loosing power?

 

[stang22]

I think you are referring to the smog pump? The charcoal cannister is mounted to the frame right below the stock air box. There is a vacuum line that runs from your gas tank to the cannister, then from the cannister to the upper intake with a valve on it. When that valve is opened up, vacuum takes the pressure off of the gas tank and draws it back into the intake.

Tim

 

[jrichker]

stang22 is right on target. Fix the charcoal canister & its plumbing & your problem will go away.

Charcoal canister plumbing - one 3/8" tube from the bottom of the upper manifold to the rubber hose. Rubber hose connects to one side of the canister solenoid valve. Other side of the solenoid valve connects to one side of the canister. The other side of the canister connects to a rubber hose that connects to a line that goes all the way back to the gas tank. There is an electrical connector coming from the passenger side injector harness near #1 injector that plugs into the canister solenoid valve. It's purpose is to vent the gas tank. The solenoid valve opens at cruse to provide some extra fuel.

 

[dls322]

Thanks for the great info!!

 

[dw89lx]

Not trying to steal your thread but, does anyone have a picture or diagram of the vacuum lines going in and out of the carcoal canister? Is there supposed to be an open hole on the top of the canister?

 

[stang22]

There are 2 big vents caps and 2 holes for vacuum lines on the cannister. If you pull the vent caps off, you would have 2 big holes, but water and everything else would fall down into it.

Tim

http://www.veryuseful.com/mustang/tech/engine/images/88Stang5.0Vacuum.gif