I'd read on this forum once, that the Prius was a cold weather favorite in Ulan Bator Mongolia, because it always starts in -50C or colder temps. I think that's due to the low viscosity synthetic oil and the way the gasoline engine is started. It was -33C outside this morning, and my car started fine without the block heater being used. I've never been one to err on the side of caution; I put a lot of faith in synthetic winter oil. My Gen 3 had synthetic 0W-20 engine oil, and it always started fine in any temperature, even down to -35C. My Gen 5 uses 0W-16, so I don't see the need to heat the engine before starting. Someone will call me crazy for sure, but I never plugged in my Gen 3 block heater, and it was in pristine condition 12 years later.
I'm setting out for the dentist just after noon. It's -6C here now. I'll be plugging our 2010's block heater in around 10 am. I use it thus year 'round. For a variety of reasons, I always buy new cars.
I could dig out the special block heater cable out from under the rear deck, and use it to plug in my block heater, like a good little boy, but after 20+ years of driving with synthetic oils, I've never seen a need for it.
They put lifts on gen1s there, Getting a block heater probably isn't an issue, but more with powering it.
From this site, with my electricity rate ($0.1097/kWh), block heater wattage (400), 2 hours use, in Canadian dollars: Electricity bill calculator | Energy cost calculator Roughly 9 cents per use. Other things to think about: Improved fuel economy, especially on shorter trips Faster cabin warm-up Less wear-and-tear on the engine (cold-starts are the toughest time for an engine) Second to last link in my signature has more info, specific to 3rd Gen Prius, but some general as well. On a phone turn it landscape to see signatures.
I don't doubt that the lube helps, but the real difference is that a Prius starts its engine using torque from its motor-generators which are much more powerful than the starter motor in any other car. Also those motors are backed by a much larger battery. If that starter can bend connecting rods in a hydrolocked engine, you bet it's gonna spin a good start on a healthy engine in extreme cold.
@Paul Gregory, I don’t think it’s been clarified: considering you’ve got the plug-in, you’re starting in regular “hybrid mode”?
I'm not sure whether the rods get bent by MG1's torque alone, or if that happens when some other cylinders fire too, or at least some good flywheel momentum builds up before hitting the flooded cylinder.. We know from a recent thread that there can be some cases, at least, of genuine hydrolocking where the ECU tries to crank and just gives up and sets P0A0F-238.
But do you compare the costs of using the block heater year around against the supposed fuel savings?
5 days a week, 2 hours usage per, year ‘round, for me, the cost for would be $23.40 CDN. Out-the-door cost of an inexpensive wine? I should maybe note: our usage is about a 5th of that; we typically use the car about one a week. Appreciate that’s unusual. Besides gas saving, have you ever priced short blocks? Anyway, you go your way, I’ll go mine. I believe new cars sold on the prairies, it’s pretty much mandatory to have block heaters installed before sale. Maybe for some reason?
If I had free power, I'd want to keep my engine at a stable operating temperature at all times. That's what they do with large scale backup generators. But doing so seems to me like it's bordering on OCD.
