9hp kawasaki surging

I have a jd gx75 with a 9hp kawasaki. It surges and won't hold a steady idle at any throttle position . When the blades are engaged then it idles fine. I took the car apart and cleaned it with carb cleaner and that had no effect also checked governor adjustment and pulled the governor spring tighter . As it surges you can watch the throttle rod that comes from the governor to the carb go back and forth like it's hunting for the proper spot.
I'm not sure what to do anyone have any ideas? I am new here and am liking the forum so far.