Many years ago, I bought a portable electric power washer to blast clean the patio and walk ways annually. I've read that these things will blast the clear coat from the surface of a car. So, I have never gotten the thing near the cars. I wash them by hand.
Now, I see that lots of people are using power washers with foam cannons. How can I use my atomic blaster, concrete pulverizing, power washer for washing the cars?