car shuts off on 1996 Cadillac Eldorado

My car starts perfectly fine but after a couple seconds shuts right off. I can restart it easily, but it shuts off every time.

2 answers
is the security light on?? if it is, then the cylinder for the key may be the issue.

you need a shop to verify.

Roy
you have leaking fuel injectors, find them and replace them if not all of them. easy to do but expensive!