What's Rain?? LOL see we out in southern california dont have rust nor do we have rain or winter, nor do we have anything like your mot test, the only thing we have is SMOG and anyone that lives in southern california will tell you the smog test's suck if you own a volvo they sometimes pass and sometimes dont then you have to get in there clean the flame trap, clean the throttle body ETC and when worse comes replace the catty to pass, wont give you your reg until you pass there " your car is now putting clean exhust into the air test " lol like its ever clean, BUT i cant complain to bad at least we in the LA area can still breathe.