As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A POWER ON STALL, THE PILOTS HAD A PARTIAL POWER LOSS. ENGINE WAS AT 65 - 70 PERCENT AND WHEN THE POWER WAS INTRODUCED, THE LEFT ENGINE WENT TO 45 PERCENT WHILE THE RIGHT ENGINE WAS AT 100 PERCENT. BROUGHT THE POWER BACK AND ADVANCED THE POWER AGAIN AND RECEIVED 35 PERCENT POWER OUT OF THE LEFT ENGINE, NO ABNORMALITIES OF THE RIGHT ENGINE. RETURNED TO THE AIRPORT AND PERFORMED A VISUAL INSPECTION AND FOUND THAT THE WASTE GATE ACTUATOR SHAFT HAD SHEARED.