Hi Richard,

This off voltage is too high, we would expect the shutdown voltage at idle to be about .6 volts. There is definitely a restriction in the fuel system, which also explains why your plane flew fine for 57 flights. I would backflush all filters and check your UAT if you are using one (or any kind of filter clunk or felt clunk). High altitude may also make the motor somewhat more sensitive to this, but it is definitely a restriction. Did you notice what your full throttle voltage was?

It is a good practice to always keep track of your high throttle max pump voltage. It will reach a normal level (anywhere from 2.1 to 2.7 depending on many factors). As the fuel system begins to clog, this voltage will start to rise, maybe .05 volts per flight. That is a sure sign of rapid clogging. 57 flights without clogging is pretty good, so once you clean everything out you will get another 40 or 50 flights, but keep track of that max throttle pump voltage!

The 2.0 ECU is OK if you are not on 72 MHz. But I would still recommend upgrading to the newest ECU.