misfiring and arcing is common with failing ignition coils and manifests as a stuttering/shaking engine. This is a regular theme on the Honda Fit boards and may have something to do with harder working small engines. Anyway, I replaced mine as preventative maintenance. If I lived out in the countryside I'd probably forgo doing any preventative maintenance but in the big city, incurring a breakdown in traffic could mean the end of your life with people speeding by you and distracted driving. I do whatever it takes to avoid mechanical failures due to my own negligence.
Live it up: There will be plenty of time to be old when you die.
** 2009 Vibe: 1.8 liter automatic **
** 2010 Hyundai Elantra Touring **
** 2007 Honda Fit Sport **