Misfire Help

[joneill1975]

My wife's 2002 I35 with the 3.5L V6 with 143K on the odometer started misfiring on cylinder 5 on Monday. I replaced all of the spark plugs and the ignition coil on cylinder 5 last night. Then when I started it up, it was worse. It was now misfiring on cylinder 6 (thankfully that is in the front and easy to get to). I swapped the ignition coils between cylinder 6 and cylinder 2 to see if it was the coil. Cylinder 2 started misfiring which means it is the coil and will be replaced today.

I thought it was odd that suddenly after I put everything back together a different coil failed.

Is this just a coincidence or is there another issue that I may be missing?

[maxhopper]

I have seen numerous instances where coils go bad around the same time. May be worth it to go ahead and replace them all instead of doing one at a time.

[Infiniti916]

The same thing just happen to me. How much did you buy your coils for.

[joneill1975]

I bought a Denso coil for about $90. So far so good.