RPMTech, the problem is that the engine is not getting enough Jet A to make it to 1300 mb CP, as it should. The reason is what is in question. Either the ECU is not commanding enough voltage to the pump, or the battery is not capable of supplying it, or the pump is old and worn out and can not supply enough, or there is a fuel restriction that is preventing enough to get through, or so on and so on.

There is no bizarre bearing noise (bearings?) at max throttle and sustained external burning of fuel in the exhaust, is there?