I was watching the news about winter car washing to keep all that corosive salt off your car. The guy also mention that exhaust from cars also etch away your paint too, not only salt. Now its way too cold to hand wash here, and I don't want to take it to a car wash either.

when the weather was good, I took the Z out for a spin, but on the way home, this busted a$$ crapmobile across the street started and a hugh *** cloud of exhaust blew across the whole street. At that moment I zoomed by. So my car now has all this dust on it, which I try to blow off by just driving fast.

Will this harm the paint, I'm still waiting till it gets warmer to wash it. I didn't get a chance to wax it yet either.