Hi all,

Im trying to resolve an ongoing issue I have been having with my 1985 corvette. There seems to be a lingering exhaust smell that I just cant get pinpoint. The engine has been resealed,fuel pump and pressure regulator new injectors, o2 sensor, catalytic converter, plugs, wires, rotor, all new vacuum hoses,
I believe the issue may be with a faulty evap system...so after some research i broke out my mityvac and did some testing. The original charcoal canister slowly loses pressure when I connect the mityvac to one of the 2 larger nipples with the engine not running. the pressure loss is really slow but its there so I think that may be an issue. Oddly when I research the electric vacuum switch I read that is should be normally closed (allowing no vacuum) but when testing mine...it was the opposite. With the engine not running it would allow vacuum through the switch but with engine running it would click and shut off vacuum. I was going to purchase a new charcoal canister, and electric switch but not sure if the switch is bad now...When I test the vacuum with the engine not running, the switch allows vacuum through it and the only other vacuum switch that cuts off flow is the mechanical switch that is controlled by the ported vacuum from the throttle body. This is when my pressure gauge shows a slow leak down ( engine not running, electric switch not energized and allowing vacuum to pass through it and the mechanical (ported vacuum switch) is closed and ALMOST blocking vacuum. Not sure if this means the canister itself is faulty and should be replaced?? If anyone has suggestions....I would sure like to hear them..so please let me know.
Thanks for all the help