1997 Chevy Cavalier Starts and then dies after a few seconds.

I was driving it and it just died, asked around found fuel pump was not coming on, replaced fuel pump. still did not come on, and would not run at all. checked some more found car has Passlock anti-theft on it. checked ignition switch, failed basic test. replaced, reprogrammed , still not starting. finally took car to dealer to have them do diags and fix. GM computers would not work on car. they told me computer was bad, replaced computer. Fuel pump comes on and now starts and dies. GM dealer said ignition switch and instrument cluster bad. will only cost 1500.00 to fix. I said no thanks. Check fuel injectors and they get pulses while car is running once it dies, they do not unless you turn off key and try it starting again. Replaced instrument cluster and it still will not start.
At this point I am out of ideas.