I used the CRC intake valve cleaner and there was a huge difference after I performed the service. However, it requires two people. I have two Berryman intake cleaners in my shop now. I will do my daughters Tucson hybrid this Spring and my car again in the Fall. The Berryman allows one person to do the service and the reviews have been good. The key is to keep up with it and do it at least once a year. I also run a catch can, but that is no solution; just a help.