Thank you for the reply. i usually apply acid with a pump sprayer. I do have a down sream injector and a double lance to try it . I really appreciate the reply being that this is my first post. I know you are on most of these threads and was also wondering whats involved in two stepping right now i brush everything and rinse. i have a high pressure soap sray but only use it when itms are really greasy with my heat. I do some box trucks that really dont need to be brushed all the time and feel like it would be faster to two step everything.