Car misses what might be the problem HELP!

I recently bought my 1994 Pontiac Grand Prix SE with a 3.1L V-6 Engine. When I first bought the car It was missing a lot when I pressed on hte gas and had a real bad idle so I replaced all the Spark plugs and wires and it seemed to have fixed the problem....untill now! as I was driving in town today the car staled on me and I had a hard time to restart it but I had no engine lights on so I pulled over in the nearest parking lot and stopped the car then when I tried to start it again it would turn and turn but I had a real hard time and when it finally started the RPM was at about 200 and the check engine light came on and then the gas pressed itself and it went up to 3000 then slowly down then the car would Idle quite rough so I came home as quick as I could and tried the same once I got here and it still did the same the only way to keep it running is to press on the gas pedal and the check engine light came off but I noticed a weird smell coming out of my car would someona have an idea as to what this could be?

Is there anything coming out of the tailpipes?
like a smokey type mix?

If so it sounds like an egr possibly?

I dunno, wait till all the big time GP guys get on this but it sounds possibly of an egr, i'm still somewhat new on GP's but i love mine, good purchase

1st thing, have the car scaned and post the codes here. 2nd thing, how long has it been since you tuned it up?

1st thing, have the car scaned and post the codes here. 2nd thing, how long has it been since you tuned it up?

Ok I got the tune Up done in october 05 when I first bought the car all new spark plugs and wires, batterie, alternator and I notice that I tool it on the highway car seems fine after an hour drive when I got off the highway is when is starts sputtering and stauling, my check engine light came on briefly but then went back off?? I really dont know I had in mind that it might be my Cat or my intake gaskets but I am not sure will try to check it out or if anyone has a better idea!