control valve
when I turn the timer to station 6, I can hear the water in the valve the cyliniod kicks on but no water goes to my sprinkler heads, if I manually turn them on untill they pop up, & then turn them off within a second or two they will pop back down, now if I dont turn them off right away & leave them on for a minute or two, they will stay up & countinue to spray untill they time out, then I can turn them on again, same thing, happens again. Can anyone tell me what my problem might be.