If possible, When you move the servo back, install a plastic push rod up to the motor. One of my ships was glitching with a metal push rod and a plastic clevice. . Bill Carpenter told me "sometimes" the interference is carried through the metal push rod. It would be a cheap fix "if" it cures your problem. The best to you with this problem.
Thanks H. Wayne.....Brian
ORIGINAL: shann
Thanks to all for the responses. The engine mount is directly mounted to the fire wall. I think I will try softening the mount some how. Possibly some rubber bushings. I am using a metal push rod for the throttle but I do have a plastic clevis on it. I think I will also move the servo back. There is a spot for it already built into the plane so it would be an easy move. I will try it this weekend and see what happens.
Shan