why is my engine making unususal noises on 1997 Lincoln Mark VIII

the other day the engine of my 97' lincoln mark 8 started making a funny clicking noise it gets louder as you accelerate, but it gets quiet to at sometimes and it cant be heard well. it pulled up a code misfire cylinder 3. i also put new spark plugs and coils in which resulted in no effect what is the problem?

Off course check the engine oil level first but you better get this checked out by someone experienced in Ford/Lincoln products in case this noise could result in something catastrophic. Hard to comment on the noise without being able to hear the noise first hand.