[hufington]

I just started using the foam cannon and it is very useful to get rid of the dirt off of the car.
I am using MJJC Foam Cannon Pro v2 with 1.1 mm orifice nozzle on my pressure washer. I am not very picky with the detergent as any decent car wash detergent that is ph-neutral would do the trick. The foam cannon is especially helpful if you have intricate design wheels as you can cover almost all of the wheel outside and inside surface with the foam that would be a PITA to reach with a brush etc.
I cover the car with foam, leave 5 mins, then rinse. Then cover again and use a microfiber brush mitt with a long handle to agitate and clean the surface and then rinse again. Use a blower to dry.