First post in way to long so bare with me. I have a Deutz 1011f 4 cylinder that starts hard when cold and won't rev up till it's warm. If i start it up and let it warm up for ten minutes it's fine. The throttle actuator is working correctly, I popped the valve cover off and rechecked the timing and it is right on ( we put a new timing belt and tentioner in it 4 months ago). while in there i checked the valve lash on int/exh all the way across the board all good. New fuel filters installed and fresh fuel. Removed the fuel shutoff solenoid and operated the rack manually and still no change. I'm running out of ideas, anyone else have a possible cause?