Learning the Quirks

The reason my car has malfunctioned a few times is due to my interfering with disobeying the proper sequences. I am used to a standard shift and this is an automatic. If I turn off my car off while it's in drive it gets angry. Seriously. I believe the electronics get confused. So I am trying to be vigilant. My car is Pontiac G6 2009. She is a great car. I am just having to learn the quirks.