2016 kia Optima - is this sound a bad ignition coil?
I notice this sound when driving, as well as when outside of the car. It seems to be louder at times, usually when driving faster. I did lose acceleration for a moment about a week ago. Yesterday, I went to start it up a minute or two after shutting off and the car started shaking and sounded loud and wrong, so I turned it off and tried again a while later and it started fine. I want to fix whatever this is before it becomes something even more expensive.