CANP is the circuit that controls the venting of the charcoal canister - the canister collects fuel vapor so to reduce pollution and under certain circumstances it is vented into the intake.
if the circuit is bad, the canister is never vented and the canister eventually gets saturated and there is a fuel smell around the vehicle, especially after you have filled the tank. the common solution is to bypass the solenoid on the vacuum hose and let it vent into the intake all the time. I did this on the red 94 and it solved the gas smell issue.