I've been working on a 89 cavalier with a 2.8 . It runs for about 2-3 seconds then dies I've replaced several things to do with the fuel system with no luck fixing the problem . I also replaced the engine control computer .

. Replace spark plugs (ACDelco only) with the exact plugs that came in the car, if they are over 3 years old.

. Consider replacing the Ignition Control Module and coil packs.

Ensure compression is good.