EGR Code, fixed - still stumbling!

[SSEiGrl92]

I was driving home from work a few weeks ago, probably going about 65mph and all of a sudden my car starts to stumble and shake. The SES light came on so I drove it right to a friend of mine who owns a shop. I pulled into the parking lot and also noticed a gas smell. My friend hooked up the scan tool and got an EGR code. I tried the cleaning technique which didn't work so I got a new one. The new EGR valve came with three new gaskets, none of which looked like the old one...so I picked the one that closest resembled it and installed it. My car still runs the same...like junk. It has a very rough idle and stumble upon acceleration. And the gas smell is coming from the charcoal canister area. I checked the vacuum lines and didn't see any cracks. Could it be a bad purge solenoid? My friend doesn't have much time to take a look at my car...so if at all possible, I'd like to try and fix it myself.
Another thing I noticed is that when I unscrew my gas cap, I am not getting any pressure release. Usually when you unscrew a gas cap, you get the air escapng before you can remove it.
Any help would be greatly appreciated.

[maxwedge]

Welcome to AF, check for signs of fuel in the vacuum hose to the fuel press regulator, the loaded cannister must be repalced at some time it will cause raw fuel to be drawn into the engine when purged, but that may be a result of another problem, also check fuel pressure and post back.