914 stalls above idle

Did the aircraft crash because the engine failed or some other reason?

When the throttle is advanced, does the Stumble and Stall happen concurrent with the power change or does the engine initially power up and then fail a number of seconds later?

Thank you, Bill, for helping me out. 

No, N702KF didn't have and engine failure on takeoff.  This accident happened at a bush strip at Owyhee Reservoir in eastern Oregon.  The low tailwheel time pilot got to close to the edge of a narrow runway and caught a wheel and took an excursion off the side.  

The latter.  When we moved the engine from the damaged fuselage to the new one the wastegate cable to the servo motor had to be removed and refit.  The cable was reinstalled and the throttle position sensor was calibrated.  According to the TCU log when the throttle is advanced from throttle position 0 to 8.3 the RPMs increase to 3300 then quickly falls off and the engine stalls if the throttle is not returned to idle.  This takes 8 seconds once again according to the TCU log that we downloaded. 

So I guess the uncomplicated answer is you shove the throttle in the engine speeds up like you would expect it too and then RPMs start dropping off.  She seems to have no trouble increasing RPMs but will not stay there.  

Well, that sounds like it is sucking the Float bowls dry faster than they can be re-filled.

I would look at a fuel starvation issue.

There is enough fuel flow for idle and slightly above, but not enough for the higher power settings.

Debris in the Filters and/or Hoses and Fittings would be the first thing to look for.

Have you checked your float bowls. On the 914 it is easy to over torque the bolt that holds them on, resulting in air leak that causes too lean a mixture at high power settings.

Ken is on to something. I have found that as a general rule, engines that start and idle fine but stall when throttle is applied do so because of too much air and not enough fuel.