gas smell

[Big GMC truck]

1984 GMC K1500
At idle, with the air conditioner on, the cab smells like gas. The smell goes away when I start moving. The carb. is not leaking. What could cause this?

 

[4xcrazy]

Mine does this, but really only when it's hot out it seems, i don't have the AC working either...

It just started doing this recently, had TPI Camaro that did it too, both mine for some reason, are building up some pretty serious pressure in the fuel system/tank, dunno why, was going to post up this question on here as well.

When you get done driving it, go back and unscrew your fuel cap alittle, and see it some pressure releases, it may be doing the same thing as mine.

Didn't mean to hijack your thread, but i am also curious as to what is causing this. Haven't really noticed it in the cooler temps, mainly just when hot out.