Ok, the problem(s) with my car is that is does one of two things: It will either (a): not start, or (b): it will start and then the engine will stall almost immediately after it starts (or run for a few seconds at best). Also, once after getting it to start, I managed to keep it running for a few minutes but ONLY because I was pumping the gas pedal quickly and continuously to the floor, and it was running very very badly then while very nearly stalling, and with black smoke coming out of the exhaust. Prior to this problem it ran like a dream, then suddenly it was like this. Any advice or help on what this could be??? I know I have mentioned two things here but it does both of these things together. For example I could work for 2 minutes on trying to start and run my car, and it will do both these things in those 2 minutes.