Do you mean air intake valve? This exact problem is happening with my "03 Impreza Outback sport. Three mechanics, new plugs, new coil, throttle chamber , etc., cleaned later nothing has fixed it. It’s complicated by the fact that for me the problem is phantom–it only occurs every second or third time I start it. I have not driven it with the check engine light on, but I know it coded once for the catalytic converter after the cleaning but has since gone. I really don’t know what to do now.