More Troubles

As previously posted I'm wokring on an 84 corvette that has sat for 5-6 years. I just finished installing a new fuel injector since the other was fouled really badly. The car does start now but not well. For instance if i have the air cleaner cover off, the car will not want to start. I may get it to start once or twice. What concerns me is the car will backfire out of the throttle body with some flames at times as well when i do this. if I put the air cleaner cover on and the start the car it turns right over and will run for a little bit before stalling out. Should the car be doing this since it has sat for so long, or do i have another problem on my hands? I need help asap!

thanks!

sounds to me like the timing is off, or it could be an ignition problem, on my 84 was the ignition module, and I also replaced the coil and the dist. cap and wires, might as well, but it was mostly the faulty ignition module. Good luck!!! :)