I just bought the 2018 PHEV after 5 years driving a Ford Cmax Energi PHEV. In the Ford, while driving in EV mode, if you floor it or turn on heater the ICE engine turns on to supplement the power demand. Once activated it will run about 2-3 minutes before shutting down - I learned that this is by design to be sure the ICE oil gets fully warmed
to evaporate any moisture before shutting off. On the Niro, in the same circumstances, the ICE comes on and then shuts down as soon as the demand is over. Is this what you're experiencing?
And perhaps that's why the Ford recommended oil change was 20,000 miles or 2 years, or when the car alerted you an oil change was required. Niro is 7500 miles or 1 year.
to evaporate any moisture before shutting off. On the Niro, in the same circumstances, the ICE comes on and then shuts down as soon as the demand is over. Is this what you're experiencing?