any way to hold EV?

If your HVAC is on and the temperature it is calling for is warmer than the cabin air, the ICE will come on to provide heat. If you are using only gentle throttle input, a slight incline shouldn't cause the ICE to come on. Try lowering the temperature to "LO" and turn the fan off and see if it makes any difference under the same conditions.

 

Even with all the accessories off, I have found that in colder temperatures the gas engine will go on for a short time even in EV mode. For example, I went on a short trip this morning in EV that was rated at 86mpg. Coming home, it was 999 (i.e., no gas at all).

 

What was the outside temperature? There is a condition if the outside temp is too low (battery temp too low?) then the engine will start.

 

Hate stating the obvious, but you do have the EV mode turned on right? Otherwise the engine is going to come on no matter what. It never turnes on in similar situations for me, even in temperatures in the hight 40s. I do have the A/C off when cold like that.

 

And as rogerv pointed out, this was with your climate controls turned off, right?

I've only had the ICE start unexpectedly when (1) having climate control "on" with temp set to something that required (engine) heat and (2) when battery was full and regenerating beyond the maximum allowed state of charge.

The only other condition that comes to mind (since its not the temperature in your garage or the battery), would be the 124 mile "ICE maintenance" start up. If you drive 124 miles on all EV, then the ICE will start to circulate the fluids.

 

for the hundreth time, if the temp is not set to 'LOW', and the fan is not 'OFF' and 'AUTO' is not 'OFF', the engine is going to start no matter the ambient air temp because it thinks you are going to want heat at some point. it doesn't wait for the outside temp to drop below the temp you have it set for, it runs the engine through the warm up cycle so it will be reay to heat if it needs to.