Just bought a brand new P20SX and now installed into an airframe. I had since fully plumbed the fuel lines, no air bubbles and re-learnt the TX. Main tank full. UAT tank full and no air bubbles.

Today out of 6 starts, only 2 starts successful, 4 starts failed..

1st start: good, grd run good
2nd start: shut down ard 200 degC can't reach stabil mode. OC: "Low rpm"
3rd start: shut down ard 300 degC can't reach stabil mode. OC: "Low rpm"
4th start: shut down ard 500 degC, popping sound from 150-400 deg C, can't reach stabil mode. OC: "Clutch" error
5th start: good....ground good.
6th start: FAILED.... shut down ard 550 degC, popping sound from 150-400 deg C, can't reach stabil mode. OC: "Clutch" error

Batteries are new and all fully charged.
TX re-learnt again.
filters are brand new and clean.
Fuel 5% oil properly mixed.
All the fuel both the start and the main fuel lines were properly plumbed and no air bubbles.

Only 2 successful starts out of the 6 starts. For 1st and 5th start, I managed to run the turbine with various throttle range, it was ok.

I did not take off as worried this P20sx turbine might quite on me...

* And btw, is it normal for a brand new P20SX delivered to me from a shop with 1hr and 30 mins of turbine hours clocked and shown on the GSU?

Can anyone advise?