anyone have tips for driving in winter? i've let her sit for a good 5 minutes warming up but i get a good but of what i guess is called "surging". the car goes "vrooom...vrooom...vrooom" over and over again making it hard to get up to speed. what is a good amount of time to warm it up. winter has only just started and this is my only car so i kinda have to drive it in winter, though i plan to avoid the salt any way i can.