ok so i was bored at 1am and decided to pull apart my engine bay, i took out the coil packs and cleaned them with silcone spray coz they were WAAAY too dirty all over....pulled out the spark plugs, and i noticed 1 spark plug had alittle hairline fracture on the side of it, but because i didnt have a spare spark plug i just put it all back together n thought id give it a run...and now its not miss firing, could cleaning of the coil packs make it stop miss firing? and should i replace that 1 spark plug?