can anyone explain how the rain harm's the finish of the car? when i wash my car after a rain it looks like pure dirt coming off. The question I have always wondered is, is it better to let the rain dry on the car(ie white spots all over car and then wash) or use microfiber towels and just dry the rain right off before it dries. the latter method will help prevent water spots but it probably isn't ideal to rub any water into the paint.

 

I would let the raindrops dry ... and wash the car normally. I don't get acid rain here in California, so I don't know that problem specifically, although I've seen some discussions on Autopia (www.autopia.org). If you're getting lots of pollution on the car, wash frequently (e.g. weekly).

Rain will not remove all the dirt particles on the car, and wiping off a dirty car with anything -- including microfiber -- will absolutely, positively put scratches into the finish. Car soap is needed to help chemically loosen the dirt so it can flow off the paint more easily.

If your car was very clean before the rain (e.g. it rained right after you washed it), you could lightly towel it off.

Just my opinion, of course. My CG TSX looks beautiful, but will show scratches easily -- hence my suggestion to avoid wiping at all costs. On silver or white you might never notice the scratches.

 

don't know if acid rain here, but if wipe rain off it is black on towel. have black car , but actually no real noticeable scratches when drying with microfiber. sometimes i let it dry and other times i wipe it off depending on time etc.. bottom line is car looks real nice and my philosophy is wax is a good thing including detail sprays which i use regularly.