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Do you guys pre-heat the prius before driving?

Discussion in 'Gen 2 Prius Main Forum' started by coolfire74, Feb 3, 2006.

  1. coolfire74

    coolfire74 New Member

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    People keep telling me that a good driving habit is to let the engine to run for couple of minutes to heat it up before driving. And I am not quiet sure if it is the case for prius, or for any other car. What do you guys think? Do you always preheat the car before you go, esp. in cold winter?
     
  2. FBear

    FBear Senior Member

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    The current crop of cars do not require warming up. Start the car the Prius will automatically start it own engine in about 30 seconds. Once the engine is going let it sit for a couple of seconds and then drive off at a moderate pace, no stomping the gas for the first five or so minutes. The only thing you need is oil pressure which the car has within 5-10 seconds of running, unless it is 40 below zero out.
     
  3. Allannde

    Allannde Just a Senior

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    I have a block heater which I use in the winter. Here in the Spokane area of Washington we only have a few days which are freezing but the mileage is better and the heater comes on quicker. The Prius stores hot water for a few days so it is protected if it is used regularly. If cost is the motive, a block heater is hard to justify. I do it because I think it is better for the engine and it is nice to have good heat right away. Lots of folks get by fine without.

    Allan de
     
  4. Karkus

    Karkus Junior Member

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    No way! That would reduce MPG. :angry:
    But seriouly, there is no need. In addition to the reasons in the previous reply, the Prius has a thermos to store hot coolant (that' the whirring noise after you turn it off). It will stay warm (for several days) and is used to preheat the engine when you turn it on.

    BTW, my winter mileage is higher this year than the past couple of years, I believe primarily because I turn off the climate control for the first few minutes whenever I start driving. It keeps the engine from running unnecessarily (and it also prevents you from being hit with cold air while the engine is warming up)
     
  5. maggieddd

    maggieddd Senior Member

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    No, just drive the car. It will warm up as you drive and it is more efficient that way
     
  6. darelldd

    darelldd Prius is our Gas Guzzler

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    "Warming" the egine beyond where oil pressure is present is a waste of time and resources (and becomes a quaint notion after you've driven a full battery EV for a while!).
     
  7. KMO

    KMO Senior Member

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    The car idles the engine itself during the first 30-60 seconds of running time - you'll see on the Energy screen that it actually draws most of the motive force from the battery while warming up, unless you push it too hard.
     
  8. coolfire74

    coolfire74 New Member

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    Thanks for you all for the inputs. As a newbie, I've really learned a lot from your guys.

    I was wondering what is that whirring noise after I turned off the car everytime. Thanks for the information.
     
  9. KTPhil

    KTPhil Active Member

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    "The car idles the engine itself during the first 30-60 seconds of running time - you'll see on the Energy screen that it actually draws most of the motive force from the battery while warming up, unless you push it too hard. "

    Yes, I noticed that--as you drive away while cold, the engine does not increase in rpm; it stays at a high idle regardelss of load or speed (as long as neither is very high).

    I imagine the light and constant load is far less strain than in a regular car, especially with a stick, where the speed changes and varying load would cause more acute friction on wear surfaces until warm and stabilized.

    This is a hard habit to get into, after decades of warning up my VWs to get the oil circulating and splashing on the cylinder walls, and the valve train stabilized. It just doesn't apply to this car. I suppose if I had a freeway onramp 100 feet ferom startup, I might relent and give it a minute. But both my commutes are downhill or flat for the first mile, so the load is nonexistant.
     
  10. Tideland Prius

    Tideland Prius Moderator of the North
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    No need to warm up. The car starts in EV mode. When the engine starts up to do its warm up sequence, you're still using battery power as the primary source. You know that because when you press harder, the engine doesn't rev up. Unless you press really hard on the accelerator, you'll be using battery. Once the engine's happy, it'll take over as the primary source of motivation.

    Also, the Prius has a 3L thermos that stores hot coolant from the previous run and that gets circulated when you start up the car the next time around. That itself (depending on when the car was last shut down and ambient temperature), can help pre-heat the engine.