430 Smoke machine for P0455 (and pending P0442) on F430

I have a F430 and recently had a CEL which showed a confirmed DTC of P0455 and a pending code of P0442. They reappeared a month after I cleared the codes.

I connected a smoke machine between the EVAP purge valve on the left and the canister to check where the leak it. I am getting smoke out of the pipe from the diagnostic pump (smoke coming out behind the left side taillights). I do not see a EVAP vent valve. In most cars the vent valve is normally open to allow us to vent when we are filling gas or the car has been sitting for some time. However, I do not see the separate vent valve in this car.

Is the diagnostic pump also serving as a vent valve in this scenario? I do not see why the smoke should be exiting out from the diagnostic pump pipe if that is not the case. If so how do you close the vent valve? I see an option in the Launch tool to open and close the purge valves, but not the "vent" valve.

Also any past knowledge as to what areas are the main culprit with these codes would be helpful. I saw a lot of posts on the 360 with these codes, but not much with the F430.

Thanks for any advice.

 

Just an update...

Since attaching the smoke machine between the EVAP purge valve on the left and the canister resulted smoke out of the pipe from the diagnostic pump (smoke coming out behind the left side taillights), I ended up removing the pipe that goes from the diagnostic pump to the canister and plugged the opening in the canister. I then re-attached the smoke machine but I get no smoke leaking from anywhere now, not even the gas cap. I am starting to wonder if the problem is at the diagnostic pump. Can it leak and cause a P0455 (and pending P0442)?

AT this point, I will need to research this more.