My EOS 40D seems

My EOS 40D seems to have really bad camera shake, in the action mode. It seems to not be focusing at all. This is really bad for me as i was to cover a local Rodeo and have just come home from taking the kids to a fun castle and getting really blurry pics in action mode.I wanted to get them jumping up and down. Today i was using 17-85mm and at the rodeo was a 70-200mm. I took excellent pics recent ly at a camp draft event in which i just put it in action mode and took great pics. i also had trouble in the local eistedford, i guess i am trying to say, regardless of whether the camera is on auto, or not the result is awfull. I have IS on the lens in the ON position and auto focus is on too.