Update...left engine still missing.
From the NTSB report.
Initial air traffic control data indicated that shortly after takeoff and while proceeding southbound, the pilot reported that he had experienced a Flight Management System (FMS) failure, and that he needed to fly straight and climb while he tried to program the backup FMS. The controller then instructed the pilot to climb to flight level 310, or 31,000 feet mean sea level, as well as provided the pilot with vectors around light precipitation. Shortly thereafter, the pilot declared a MAYDAY, stated that he was having difficulty with the backup FMS, and that he was hand-flying the airplane. At this time the controller issued the pilot a no-gyro turn to the left to avoid precipitation, after which the airplane's airspeed was observed to fluctuate significantly. The airplane was then observed turning to the right before the radar target was lost. There were no further transmissions from the accident airplane.
The airplane's wreckage was located in open, flat pasture ground, about 1 nautical mile (nm) southwest of Cedar Fort, Utah, and about 28 nm south-southwest of SLC. A survey of the accident site revealed that the linear debris path of wreckage extended for about 1 nm on a west to east orientation. All of the airplane's primary flight controls were accounted for at the accident site. At the time of recovery, the airplane's left engine had not been located, however, search efforts remain in progress.