I was glad to see an over the counter intake valve cleaner. I tried this on my 12' Focus. The directions say to keep engine at 2500 rpm and spray built in straw cleaner into the throttle body past the mass airflow. Specifies that mass airflow could be damaged. with intake boot off car would not maintain any rpm steadily let alone get up to 2k . It would sometimes flash above or bog down. So called CRC . Tech said to try with boot in place. This would put the straw right at the mass airflow wire. So I did short bursts , Then started, For fear of hydro lock.Seems to have worked . Car runs better and blew out an huge smoke cloud when taken out on the road after the hour soak waiting period. Wasn't having any driving issues before. But figured there might have been a gradual performance decrease not perceptible. Anyone else use this product?