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This is my first hybrid vehicle so I'm not really sure about this so will post this for you smarter guys to let me know.

Now that we are having some mornings that are as cold as -10C I of course want to let the engine warm up for a couple of minutes before driving.
is there any place where I can see the engine temperature so I can see if the needle is still at the bottom for cold or in the middle for warm? Or is that somehow different for these hybrids?
 

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Hybrid Assistant phone app shows ICE temp and a lot more.

 

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This is my first hybrid vehicle so I'm not really sure about this so will post this for you smarter guys to let me know.

Now that we are having some mornings that are as cold as -10C I of course want to let the engine warm up for a couple of minutes before driving.
is there any place where I can see the engine temperature so I can see if the needle is still at the bottom for cold or in the middle for warm? Or is that somehow different for these hybrids?
The HV system has 4 distinct ICE thermal states. The actual coolant temp is relevant to which state you're in, but not really something you need to concern yourself with. There is absolutely no reason to "wait a couple minutes", you're just wasting fuel. The ICE will shut off anyway if its not moving. Anyways, the synthetic lube is completely fluid at all temps, so just start it and go.
 

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Heated seats and steering wheel. Start and go. Don’t “warmup” the vehicle.


Sent from my iPhone using Tapatalk
 

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The HV system has 4 distinct ICE thermal states. The actual coolant temp is relevant to which state you're in, but not really something you need to concern yourself with. There is absolutely no reason to "wait a couple minutes", you're just wasting fuel. The ICE will shut off anyway if its not moving. Anyways, the synthetic lube is completely fluid at all temps, so just start it and go.
Even when it gets to -30C you wouldn't let it warm up at all?
 

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That 0W-16 oil is thin as water. Start and go. Drive easy for the first few minutes if you want and it’ll be fine.
 

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I never even think about warming up, just get in, start, buckle up, and go. As they are saying, the new oils flow so quickly you never have to warm up unless there is ice or snow on the windows and then the warmup is to defrost.
 

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Ok thanks for the info everyone. I don't want to give away my age too much but when I think of oil I think of the 10W30 I grew up with and making darn sure the vehicles were warm before we started driving. ;-)
 

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Even when it gets to -30C you wouldn't let it warm up at all?
There's a cogent argument for saving a little bit of gas by letting it sit and run for about 2 min before starting off in super cold temps. This is to avoid driving the ICE in "open loop" mode where it sucks down a lot of fuel. It also has the advantage of providing a little heat wherever its needed. But as far as engine health, it does nothing. There's plenty of things in a car that suffer in the cold, (including the driver), but the ICE isn't one of them.
 

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Under these conditions there is all kinds of electronic magic going on to bring everything up to temperature including battery heaters, engine coolant and oil temperature management, de-icers, air conditioning. Unless there are some specific recommendations in the owners manual I doubt that you can second guess the systems. If you would like to monitor exactly what is going on the android "HybridAssistant" app is very comprehensive. It works in conjunction with a Bluetooth OBD reader which can be bought for about £55 in the UK. If, for your own comfort, you want to leave the vehicle warming up in "ready" mode I can't see any harm because the engine always runs at optimal efficiency to reach and maintain the correct running temperature. You will be using some fuel to achieve this but not at the expense of engine wear as could be argued with a conventional engine.
 

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The Prius hybrid line will try very hard to use traction battery and electric motors to move the vehicle while the internal combustion engine (ICE) is warmed up with cylinder ignition timing to minimize power output until coolant is at/above certain temperature. This is how the hybrids avoid the a lot of emissions normally associated with ICE warm up. I can only assume that the Rav4 hybrid works the same way until I take delivery of my 2020 Rav4 hybrid and I can check for myself using Hybrid Assistant app.

That said, using the traction battery and electric motors exclusively to move the vehicle for the first minute (approximately) in very cold temperatures can be taxing on the traction battery. The Prius (and I assume Rav4h) have a ways of dealing with cold battery temps; heating strips to keep battery above 34F, reducing max battery draw, and finally letting the ICE to contribute power during early warmup as a last resort.

I’m going to find the Rav4h deep dive engine video and see what I can learn from it. Here is the rear electric motor deep dive;

We get very cold winter days here near Syracuse NY and we don’t warm up our garage housed 2012 Prius v or 2017 Prius Prime. On cold days I try to take it easy on my Prius v, driving slow-ish up the hill from my driveway to the main road. The engine is warmed by the time I get on the main road and contributes power to drive system. We have also noticed that the Prime (trying to run in EV mode at moderate 40mph and below speeds and AC heat off) will start and warm up the ICE around temperatures of 10F to keep the battery happy and healthy.
 

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I use a near 20 year old (old firmware can be updated by sending unit it for upgrade) ScanGauge II in my 2012 Prius v, but it causes problems for the center display and lights up warning lights on wife’s 2017 Prius Prime. So I bought one of the expensive Bluetooth adapters recommended by Hybrid Assistant web site and that has been a joy to use on both vehicles with the free Hybrid Assistant app.

In my Prius v, I like to monitor Internal Combustion Engine (ICE) RPM, engine coolant, brake pad pressure, and fuel level. I educated myself on the stages for engine warmup (S1 - S4) and corresponding coolant temps, to see when the ICE is ready to provide power to locomotion. I enjoy watching Toyota improving the regen to physical braking switching over our 4 Prius models (Gen II, PiP, Prius v, Prime). And I like to see exactly how much fuel is in the tank and have run it down to 0.3 gallons to drive 60 miles after refuel light goes multiple times.

On the newer Toyota models, you can also get actual individual tire pressure readings from the Bluetooth adaptor with the right app.

Here is a good run-down of apps; https://caristaapp.com/supported-apps
 

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I like to see exactly how much fuel is in the tank and have run it down to 0.3 gallons to drive 60 miles after refuel light goes multiple times.
I have used HA for about 2 years, and I didn't know that HA could view gas remaining. Where is that meter?
 

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All cars should have coolant-temperature gauges. I quote from an article online by Bengt Halvorson: "
For the truth here, look at nearly any vehicle owner's manual; most advise against revving an engine too high when cold, for good reason. The alloy parts of an engine don't fit together in quite the same way until fully warm, and the oil pump has to work especially hard to get oil into the smallest spaces when the oil is thicker.

And with the thinner oils being introduced this year and over the next several model years—allowing better fuel economy and good high-heat protection—they counterintuitively place engines under higher stress in cold starts."

My cars all have engine-temperature gauges, and I look at them always when starting out driving when the car is cold. I try not to get the revs high (above 3000-4000 rpm) until the engine is at normal operating temperature. This is a question of taking care of your car so that it lasts many years without major problems. I also do not like getting hybrid cars that do not have traditional tachometers, and cars with ICEs that have no temp gauges and no tachs will always struggle to get my money for a purchase.
 
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