Intermittent rough running and RPM drop
Climbing at full throttle 912is after about 1 hour flight and than really rough running and rpm dropped to 4100 still at wide open throttle (WOT). Reduced throttle to idle and OK. Back to full throttle bad vibration and only 4100 rpm. All gages norma, 1 and 3 EGT slightly lower but nothing unusual…... Landed, shut down, restart, systems check, all ok. Takeoff power ok for about 5 seconds than same problem, rpm drop and bad vibration. Landed, tried again 2 more times and same - full throttle ok for 3 to 5 seconds than rpm drop and bad vibration.
Pulled off runway, pulled cowl off, wiggled every plug, electrical connection, fuel injection wire twice. Started up ran fine all the way home 40 minute flight.
Down loaded with BUDS dongle and nothing for the ECU time of the flight. No warnings, faults, nothing.
Thinking back, I should have shut off one lane while flying to see what happened.
Next step is to fly with the BUDS system to look for any thing in the engine health screens and shut of lanes individually if the problem happens again.
Any thoughts, experience?
