Hello, i have a 2006 lancer es, manual trans with 80, 000 miles on it. About two weeks ago the car began hesitating on take offs, and after changing gears, mainly at low rpms. A couple days of this and the engine light came on, so i took it in for a diagnostic check, and it came up as cylinder 4 misfire. I recently changed the spark plugs, but figured i would again to see if it helped. I put in some platinum plugs and it ran great for a week, but is now back to the hesitating. I pulled all the plugs, and they are properly gapped, and appear normal. The plug wires appear fine, should i now try to change the two ignition coils? I have a appt set up at my dealership to have it looked at, does anyone know if i will be charged to have it looked at, eventhough it still is under the limited 100,000 mile warranty? I told them i thought it could be a bad cylinder, so mainly want them to check that, which is covered under the warranty.
Thanks, Phil