As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THROTTLE CONTROL WAS PURCHASED NEW FOR ENG CHANGE AND INSTALLED AND RIGGED IN ACFT. AFTER TEST RUNS ON ENGINE, CONTROL STARTED TO STICK IN HALF THROTTLE POSITION. AFTER DISCONNECTING CONTROL FROM ENGINE, IT WAS FOUND THAT THE CONTROL CABLE WAS DEFECTIVE INTERNALLY. CONTROL REPLACED WITH NEW CONTROL CABLE. ENGINE TEST RUNS COMPLETED, THROTTLE CONTROL WAS SMOOTH. DEFECTIVE CONTROL RETURNED TO SPRING AVATION FOR WARRANTY.