87 buicl lesabrs 3.8l vin code 3 eng has a miss

car has new plugs wires ing module 3 new coils still has a miss on cylinder 5 where to i turn to next?

Run a compression test to see if this cylinder is lower on compression than rest of cylinders.

Should also have #5 fuel injector checked if equiped with them.

A compression test should always be the first step in diagnosing an engine performance problem; even if the engine only has 30k miles on it.