Strange ICE behavior

I drive EV pretty much every day with some afternoons at 100+ degrees and the AC blasting. What mode are you driving in -- Eco, Sport, or Normal (neither Eco nor Sport)? In Eco mode it's pretty easy to avoid the ICE coming on -- you can press the accelerator up to but not beyond the detent and stay in EV mode. In Normal or Sport mode the ICE will come on before the detent (basically when the power meter goes beyond the blue zone); I suspect that's what happened. Once the ICE comes on it will stay on until warmed up (5-10 minutes).

 

Normal. Just started the car and drove. No Eco, Sport, or HV selected. Driving down the freeway on a level stretch of road at 70 mph with cruise control on. Not accelerating or decelerating. Maybe it was just doing a system check? It may have come on while coming down the incline from an overpass which would have been just before she noticed it on. If so, would have been after about 2-3 miles after leaving work with a full charge. That would suggest the possibility of the regen braking behavior. Can't be more specific as I was not the driver and I'm going on what my wife was aware of at the time and remembers now.

 

Since you haven't had the car long, we don't know when the last system check was done, so maybe. Or the driver dipped into the range where the ICE triggered. It only takes once. I wouldn't fret unless it becomes a common occurrence.

 

70 mph with heavy AC usage is a gray area with regard to ICE coming on and could well be expected to call for the ICE (see p 13 of the manual). Were you in SPORT or ECON? That will make a difference too.

It could also have been a System Check. If the Power Meter turned completely white with no blue at all, it was probably a System Check. Those are infrequent and usually only last long enough to get the engine up to operating temperature unless you short circuit the process by turning off the engine before it’s completed. I wouldn’t be overly concerned about it. I drive almost exclusively in EV and the occasional short ICE runs don’t even cost me a bar in the gas gauge between HV trips (as much as 9 months between). I don’t begrudge these very infrequent ICE runs since it’s a PHEV and it’s keeping the engine lubricated and ready to run whenever I need it (which for me was <17 gal in the first year).

 

Thanks for the manual ref. No on the Sport or Econ. Just plain EV. Doesn't the power meter turn completely white whenever the engine is running? or does it look different when it is doing the system check? The ICE only ran about 5 minutes and used up 6 mi of HV range. Not sure how soon or often it will do system checks. We got the car last Wednesday and are at 800 miles. (500 last Wednesday driving back from Lockport, NY where we bought the car.)

 

That means that the engine ran last Wednesday, which rather rules out the idea that it was a system check.

 

I got in the car this morning to move it off my wife's work's charger and noticed that the air flow was set to the button on the far right - defrost and feet. I switched it to vent and feet. I wonder if the air flow setting caused a heavier climate control load with our 87 degrees and high humidity. The ICE did not run on her way home tonight. Same route, same charge, same time of day, pretty close to same temp and humidity.

 

While I don't really believe that this is the explanation, it's a good illustration of the kind of obscure thing that could be. The word that triggered interest was "defrost". Even in hot weather, defrost may trigger a request for heat, and that might trigger an ICE start to get waste heat from the engine. This is pure unadulterated speculation on my part, but I do know that when you hit START on the car at temps below 15°F that it immediately starts the engine to heat the cabin to avoid pulling yet-more energy out of an already-degraded battery. So it's not as far fetched as it initially may seem.

 

I finally got the ICE start after full charge while going downhill (after a year and a half of ownership).
Engine ran and warmed up to 157 degrees F. then shut off, approx 5 minutes.
Warm summer day with AC on.
Ran about 50 miles in HV earlier in the day, so injector gas was fresh and tank was fresh.
Engine was cold (ambient).