I have the PolishedBliss cannon and have been using Adam's car wash. It seems to foam fine, but by the time I get done doing the whole car and come back around to the side I did first, it's all running down and dripping off. Is that a problem of the soap or is it just the way these are? I thought I could get it to stick there for at least a few minutes.
It'll depend on the soap, how open/closed the knob on the foam cannon is, how hard your water is.. there's about 500 variables that will impact how well a foam cannon works for you.
I'll try that next time. I think around 2-3oz soap, the rest water. I shake it and open the knob all the way for max foam.
Try 4-5 oz of soap and fill the cannon with warm water instead of cold. Also, after you attach the bottle to the top, shake it up good before attaching it to the powerwasher