Worse, since Kioti is a small player in the broad diesel industry, universal diesel code readers do not support Kioti. All to say that anytime the "right to work" legislation comes up, vote, "YES!"
I tend to agree with your assessment: something is lying to the ECU that eventually causes the ECU to trip into limp home mode. While not directly related to Sean2202's problem let me tell you a Kioti limp home mode story: In 2014, when I first got my NX, my tractor went into limp home mode because while the ECU claimed it was regenerating (every 8-12 hours), it never got the engine high enough up to temperature to complete a regeneration cycle. As a result, my new 60hp tractor was absolutely gutless. At the time I was super frustrated, and any negative thing said on these forums was ridiculed or deleted. My fix for the poor running condition, as well as the diesel industry fix (because fleets were experiencing the same problem as the limp home problem was a Tier IV spec problem and not just a Kioti problem) was to install a warmer thermostat that allowed the engine to run at a higher minimal engine temperature, one that was warm enough to
1) Stop the engine from continually running on the warm-up fuel map thereby plugging the DPF at a much faster rate, and
2) Also allowing the engine to be warm enough to fully complete a regeneration cycle so the machine wouldn't eventually get tripped into a limp home condition because the DPF was plugged up.
Here is a video of my frustration with my tractor in 2014 before I puzzled out the problem and installed that warmer thermostat.
Also, I should add that if the thermostat has a spring-loaded bypass, then that too can cause the same problem with excessive warm-up times while in use as the coolant can overcome-that weakening spring-loaded bypass and slip right by the thermostat entirely. The condition will act similar to a T-stat being stuck open.