I have been having a stumbling problem with my car once it warms up. A mechanic had a real quick look at my car today, he discovered gas in my fuel vapour cannister, he also said that there was too much pressure building up in my fuel system(after he took off my gas cap). What would cause excessive pressure to build up in the fuel system?What type of drivability problems are typical of such a problem?I take the car back to this guy Thursday for a more in depth analysis

------------------
1990 Iroc convertible,305 tpi,Black with black leather interior,lowered,Taylor 8mm wires,K&N's

 

Zed,

There is a pressure control valve in the system (usually near the tank) that is supposed to regulate tank pressure. Beyond that, there is a relief valve in the filler cap that is suppoesed to act as a final safety valve for excessive pressure. If the EVAP is saturated, make sure the purge system is operating correctly. If the EVAP is getting slugged with fuel, you may have a failed pressure control valve at the tank.

------------------
Later,
Vader
------------------
"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

sounds like the vapor canister went south. You filled the tank up to high and let gas get into the pressure lines that go to the canister filling them up and then having the pressure no where to go. I say replace the canister.