Pontiac Repair: 2000 Pontiac sunfire, pontiac sunfire, car wont start

Question
Hi there, I had my Pontiac for ruffly six years now and not a problem since. Then with in the last year my car started to stall while on the road it only did it twice last year in the winter and I'm talking -35 tops. I just got a tune up on my car in December of 2010. And that unleashed all the demons my engine was encasing. My car has stalled on me a lot more then ten times while driving it, since the tune up. Practically every three to four days my car wont start. I could drive it to work and at the end of the day I'd try to start it and nothing..My mechanic thought it could be the starter but now I'm thinking not. He also thought it was lose wires but there's still the same problem. I had to call a tow truck every week in February. It does not matter whether the gas is full, half, or close to empty same problem. And last night puts the icing on the cake for me. It was about -28 out yesterday I was able to drive home in my Sunfire no problems everything was good. Then about forty minutes later we left for grocery's. My boyfriend was driving. He went around the corner fast I thought it was him being a jerk but he said the car speed up. And then the motor started to rev really high. And we started to speed.  My boyfriend was trying to press the breaks to slow us down but the car keep speeding up and he said the gas peddle went down. I saw that the amp went to 6 or 7 and told him I'm putting it in neutral put the hazards on. Mean while the motor was still revving high, he went to the side shoulder as best as he could. I put the parking brake on and put it in park. And he shut to car off. We sat there for ten mins thinking ok what the heck happened. We tried to start the car and it was still revving high. So we shut it off called my brother he looked at the car. Played with the throutall or the mechanism that rev's the car. Took it for a drive around the corner. He had to drive it back to our house because the car stalled at every break and stop they made. And now I see so many concerns that people have over their Sunfires of any year and model I thought I should voice mine. Last night we could have ran a person over or got in a car accident because of malfunctioning parts these cars are having. My life and another life could have been ruined. I fear to drive my car now and I am afraid that the problem will not get fixed. If you could possible help me.
My car is a 2000 Pontiac Sunfire 2.2l engine 4dr automatic, standard edition with no power windows.

Thank you
Andrea

Answer
Hi andrea:

well first off I would have the car scanned for codes. any of the big box auto parts stores will do this for free. see what codes are stored and go from there. this can be any number of things causing this. It sounds like you have a few things going on with this. One thing I can tell you is this car was invloved in a recall down here in the states for multiple engine computer issues where a shild was installed over the computer and the computer sealed up. If that recall was never done and it is indeed a recall in canada as well get it done. call any GM dealer and give them the VIN# and they can run the # to see if it has been done or not. That is where I would go first off.