1991 Buick Century

It had a minor tune up I mean just spark plugs and spark plug cords. That was maybe 2 years ago. No, my brother is a mechanic at National Tire and Battery (NTB) in illinois and he came to ohio and that was what he concluded. He was able to get it started here at the house but backfired and stalled. He adjusted the idle because it wasn't a smooth idle. And that had it run alittle longer but still backfired and stalled so we took it to NTB and had them put that stuff on. I don't know if they checked but I doubt it we didn't tell them to check but they said after that they didn't know what else they can do. After putting that stuff in the car they got it started and was able to drive but still backfired and stalled after a few minutes of driving. And befor acturally getting this stuff done when I tryed to start it. Their was a strong smell of gas. I most likely flooded it. But if that helps. Sry for the length.