check engine light flashing on 1996 Chevrolet Cavalier

It seems as if my car is running on 3 cylinders. The check engine light keeps flashing at me. I have changed the spark plugs and plug wires in vehicle already. Does anyone have any suggestions on what could be the cause of the issue?

1 answer
plugs, boots, coils and cap carrier are usually replaced all together. common failure.

Roy