Thank you to all that replied. I finally had some time to look at the charcoal filter, I pulled the bottom hose off the filter and there was what looked like a small amount of dust at elbow. The other end 9 to 10 inch away when goes into the frame, so I pulled it out. The hose was clogged with what looks like dirt. I broke free the dirt and reinstalled the hose. Now the end of the hose is cut at an angle and looks new,  it goes into the frame of the van just stop. Should there be other hose taking it some place.
Thanks again.
Kevin Plichta

> Date: Thu, 11 Sep 2008 19:53:38 -0400
> From: plichtakevin@HOTMAIL.COM
> Subject: Gas tank sucked together!
> To: vanagon@GERRY.VANAGON.COM
> 
> My 91 is having a problem with the gas tank being sucked together. I have noticed that when I open my gas cap that it is very hard to pull it up and air is being sucked in, a very tight vacuum. I am not sure where or now air get into the tank after gas is used? From expansion tanks? Carbon filter what its roles is? I would like to figure out where air should be going into the tank to see what's plugging it.
> Thanks again for the wisdom!
> Kevin Plichta 
> 
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