It seems like last time I washed my sister's car (she never has her car's paint sealed or waxed and even washed very rarely), all I did was do a big general purpose cleaner pass (with OPC) and then wash it (with ONR). I saw the car about 4 months later and it was a lot dirtier than it was before I cleaned it in the first place. She parks outside in a subdivision with a lot of trees around. The dirt cakes on when she doesn't wash it. And, it was even caked on a lot worse than usual when I saw her car again.
I'm really wondering if the reason the dirt caked on more after I washed it than before was because the OPC stripped something off that was protecting the car somehow? There was definitely no LSP on there when I started washing it. But, even without LSP on it to begin with, does the OPC make the car's paint even more vulnerable to dirt than it was before?
She usually just washes her car with a pressure washer at one of those coin slot places, doesn't even use the soap and the brush wand (that will nick and scrap your paint all to hell and back). I'm thinking that pressure washer doesn't leave the paint more vulnerable, but the OPC does?
I'm really wondering if the reason the dirt caked on more after I washed it than before was because the OPC stripped something off that was protecting the car somehow? There was definitely no LSP on there when I started washing it. But, even without LSP on it to begin with, does the OPC make the car's paint even more vulnerable to dirt than it was before?
She usually just washes her car with a pressure washer at one of those coin slot places, doesn't even use the soap and the brush wand (that will nick and scrap your paint all to hell and back). I'm thinking that pressure washer doesn't leave the paint more vulnerable, but the OPC does?