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With AC turned off it seems I've got more power

Discussion in 'Gen 3 Prius Fuel Economy' started by murigius, Oct 27, 2010.

  1. murigius

    murigius new but learning

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    Out of (bad) habit, I've just automatically left my AC on the past month I've had my 2010 Prius. I turned it off this morning and was surprised at the obvious boost in the car's power. It still ran in the ECO range, but with lots more zoom. Now that the warm weather is leaving the SF Bay Area, I might get used to leaving the AC off!

    My last 2 MPG's were 50.0 and 45.9 I'm hoping to see an increase w/o the AC on all the time.

    Has anyone else experienced a difference in performance with/without the AC.
     
  2. Erikon

    Erikon Active Member

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    Not that I've noticed. The AC is electric, no belt drawing power off the engine so the ICE shouldn't care one way or the other. However, a low battery will affect your performance, so if you are now running with a higher SOC due to not using the AC, that could help!
     
  3. chrisj428

    chrisj428 Active Member

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    Could be the obecalp effect from the way the power is routed to the compressor through the effning diode.
     
  4. Joe166

    Joe166 New Member

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    You need to adjust your tin foil cap. It is probably holding you back.

    Seriously, unless your battery is low and being charged, there should be no relationship between A/C and power.
     
  5. murigius

    murigius new but learning

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    Thanks guys. A little humor has helped with the obecalp effect in the past. Now I know that there's no connection --barring my aluminum cap not being on quite straight-- between the AC and the power that the engine puts out.
     
  6. LeadingEdgeBoomer

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    Obecalp effect? Is this related to the critical danger of dying from di-hidrogen oxide?

    What they said. In addition, in cold, humid weather (or if you breathe in the car in really cold weather), the inside of the glass can fog up. I don't know if the heating/cooling system uses the A/C to help dry the inside air. In older cars, running the A/C manually used to help.
     
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  7. V8Cobrakid

    V8Cobrakid Green Handyman

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    the a/c system does cycle the compressor to keep things from fogging up. there is a humidity sensor.

    in theory, any electrical draw has to be replaced.. therefore, it's possible that it makes the car slower, as power is being split off of the pack to run the compressor and fan. it's a little unlikely to be felt too much... but then again.. when you're running with such high efficiency, little things add up fast.
     
  8. murigius

    murigius new but learning

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    Thanks, V8Cobrakid. I've put a little over 1K enjoyable miles on the Prius, all with the AC running. I 'did' notice a measurable boost in power when I decided to turn the AC off due to the cold morning. I'm going to go through a tank of gas with the thing off just to see if my 50 MPG improves.

    The windows haven't been fogging up like they'd do on my former Solara when I'd switch the AC off. The Prius seems to be smarter where airflow is concerned.
     
  9. chrisj428

    chrisj428 Active Member

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    And here I thought I was the only one who'd heard of the dangers of dihydrogen monoxide! That stuff is horrible! Causes death, highly corrosive, causes erosion, etc. and seems as though nobody's heard of it! The worst part -- it's everywhere! :jaw:Here's a link for more information.

    PS: :pop2: ;)
     
  10. wick1ert

    wick1ert Senior Member

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    I have also noticed decreased power during acceleration around town with the A/C running. It was a killer on my FE this summer during my drive to/from work.

    As someone else mentioned, it's an electric compressor and receives its power from the battery. I don't know for certain, but it seems as though the battery management is probably allowing less power from the electric motor when the compressor is running.

    I wonder if this is something that can be monitored via a Scan Guage or not. It would be interesting to see if this was indeed the case.