My SES light came on a couple different times. Both under hard acceleration. Tried to pull a code with my Predator, but no code was ever thrown. Took it to a Ford dealership mechanic my friend knows and all he could find was that I had a screwy o2 sensor, but since it never threw a code, the dealership could'nt do anything about it. The SES light has'nt come on since, but my warranty expired last November. Only 17K on my Mach.