Evaporative Control System

["Robert Rooney" <dmcvegas@xxxx>]

When ever I increase the idle on the engine, the carbon canister 
doesn't appear to purge itself of the recovered vapors. The odd part 
about this is that if I manually apply a vaccum to the canister, the 
engine will rev up as the vapors are released and burned. When I rev 
the engine I can feel a good vaccum from the hose the connects up the 
intake manifold. But it is not as strong as the one that I have to 
apply to open the canister. From this I have 2 questions: 1. Is this 
normal and theres a problem w/the vaccum line, or does having to 
apply a STRONG vaccum to the canister an indication of it being 
defective? Any ideas would be greatly appriciated!

-Robert
vin 6585

p.s. I really do need to remedy this as quickly as possible. After an 
hour or two out in the heat, the gas tank begins to build up an 
excessive amount of positive pressure. On Friday when I pulled into 
my garage I had to remove my gas cap just relive all the pressure. 
While doing so the tank acctually creaked as all the gas fumes rushed 
out!