I was casually chatting with a friend of mine and something in the topic led me to say "yeah in winter i usually start my car up, and let it idle for a good 5 - 10 min before i jump in and drive so it gets warmed up". my mechanic friend said "that'll really mess your car up, you shouldnt ever let it idle like that, not with a 4.6 at least". what the hell? this is contrary to everything ive heard, and to all logic that i've come to know. does there any bearing or truth to what he said? thanks.