Prius Prime in very cold weather

stop breathing so much?

 

Wow. What a bummer. I'm a bit further south than you but it can on rare occasions get
to -25F here in Chitown..
If I encounter your situation I think I might invest in something like this:
https://amzn.to/2M2A4Bu
J

 

Maybe check that your coolant is getting up to the correct temperature? You'll need some kind of OBD tool (or just an infrared thermometer if you can stand going outside and looking under the hood in that weather). It could be a problem with the thermostat, if these cars still have one. The last car I had, had a known issue with the thermostats that would prevent the engine from completely warming up in very cold weather, but it wasn't noticeable most of the time. On a -15F morning I had to hold the engine at 2500 RPM while waiting at a traffic light, to keep the coolant temperature from dropping, and to keep my hands from getting frostbite. The temperature gauge barely moved past cold on my 20 minute drive to work, and that was after letting it warm up for 20 minutes in the driveway.

Also check the grill shutters. It's possible that they got stuck open because of ice, sending lots of cold air into the engine bay.

I haven't driven the Prime in weather that cold, but so far the heat seems strong enough on the highway with the engine running. The heat pump is really weak in EV mode near 15-20F, and it takes forever to defrost the windshield, but if the engine is running that provides heat.

You probably tried this, but make sure to set the temperature high (at least 74F), turn off eco mode (probably has no effect with the front defrost though). And it might help to push the front seats only button (if you don't have rear passengers) to keep the heat in the front.

 

Not often, but I sure have had some sub-zero temp last winter but never had frost develop inside of windows. There has to be moisture inside to cause that to happen. That said, I have to admit, PRIME is not the most comfortable car to drive in extreme cold. Even with ICE providing heat, it never warms up as quickly as my other cars or even compared to previous generation Prius I owned. We are expecting sub-zero weather this weekend for the first time this winter. I am not looking forward to scraping the frost off of my PRIME, but that's only for outside of windows.

 

Sometimes it happens if the floor mats are soaked from snowy boots. Not sure what to do about it except go for a long drive to dry everything out, or bring the floor mats inside to dry.

It makes sense that if the car is burning 1/3-1/2 as much gas as a regular car, it would be making less heat. At least the seat heaters get nice and hot. I've noticed that if the heat is on, the car will run the engine more often than it might normally.

Those little 12V heaters might help a little, but the accessory outlet is limited to 120W which isn't much heat. Maybe rig up an inverter and one of these for more heat. Or plug it into a separate circuit in the garage (not used for the EV charger) and use it to pre-warm the car like a block heater. amazon.com/Zerostart-2600900-Interior-Electric-Portable/dp/B000NM73ZA/

Speaking of block heater, it's not a bad idea to add one if you live somewhere that gets often extremely cold.

 

Using recirculate is a common self-inflicted problem most people aren't aware of. You must pull in outside air to help keep the interior of the car dry.

I never encounter problems like you describe here in Minnesota with that knowledge. Keeping the doors opened an extended time while you exit will help the humidity is escape to.

We parked outside last Christmas in Wyoming where the car sat outside at -9F overnight. No big deal.

 

+1

Nexus 7 ?

 

I am in the Duluth MN area and going through a 2nd winter with my Prime. I have never experienced significant issues with inside frost even with 4 people in the car. (And no they are not holding their breath or breathing through straws stuck out a window although it's a thought.) I think that heat in EV mode, when outside temperatures are below 15 degrees, is without question - minimal. Takes the chill off and not a whole lot more although seat and steering wheel heaters help a lot. My work vehicle, a Sequoia, has excellent heat that can drive you out but compared to my Prime takes way way longer to really get up the heat in the cabin. Lots of ice cold metal to warm up I suppose.

With the ICE running I find the heat in my Prime comes up quickly and is more than adequate even in sub zero temps, dare I say almost toasty. I would guess the Prime with the frosty interior and limited heat has an issue that needs to be addressed. It will be interesting to hear what the fix is - assuming one is found. Good luck.

BTW I have yet to see another Prime on the road in this area. Very un-California like but then right now many of our roads are like hockey rinks in serious need of a Zamboni.

 

I find charge mode handy for making extra heat provided your battery isn’t too full ! Seems to create enough extra of heat to keep the wife happy !

 

Very cold weather observations: From cold start at -22 deg F ICE (Coincidental acronym isn't it?) reached operating temp in only 1.7 miles. Compared with other vehicles I have driven this is really quick, likely the result of using exhaust heat to speed the process. Looking like a great idea, particularly in this weather. Given the cold start and short trip mileage is pretty good too I think.

Seems to me that in these really cold temperatures, running the ICE, acceleration feels noticably quicker as well. Seems counterintuitive but I have observed this a few times. Perhaps Atkinson cycle engines like really cold dense air? Has anyone else noticed this quickness? Could be my imagination or wanting to hurry to the next warm destination.

Yes, the steering wheel heater is on. When it admonishes me to use a more moderate temp, that ain't happening and in the Eco dashboard the sheep are nowhere to be found even though they have a built in winter coat.

 

All engines should like really dense air, which happens naturally in really cold temperatures.

I missed this thread the first time around, but interior icing was always a problem back when I was young and these arctic blasts were more frequent. We just had to learn how to deal with them, which involved making sure moisture got flushed out of the car before it could freeze on the inside window surfaces.

 

Toyota invested quite a bit with regard to rapid heating. That's very important for emission cleansing... which also benefits cabin warming. Sadly, most people never notice.

 

AC use causes an accumulation of moisture, that tends to dump at the next start-up. Some people using AC year 'round?

 

Good point, I also found that sponging out the ponds of water collected in the all weather floor mats helped a lot, more so in these very cold conditions.

 

Modern climate controls often use AC as part of the defogger/defroster function, so that accumulation can still happen even without the operator intentionally turning on AC.

But I remember frost on the inside of windows way back on cars entirely lacking AC.

I don't sponge it out anymore, but instead take out the whole mats, pour the water on the ground, then hang the mats inside the garage to dry.

The spouse used to keep a towel inside the car to sponge off the inside windows each morning. Of course, the moisture in that towel would later evaporate, then re-condense on the windows again, forcing re-sponging every morning. I made her take the wet towel out every day, to dry out somewhere else.

 

All the cars have the same problem. Not just Prius Prime.

 

Prius Prime copes with it extremely well... as my newest video confirms:

 

Same issue today, my driver side window has ice on the inside. Rear windows fog up very fast too. Not even 3000 miles on it. Think the Dealer can or will do anything?