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had a 3mpg jump on the cons after a red light stop

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

  1. priustexasbob

    priustexasbob Member

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    I took the first long trip today. I zeroed trip B then backed out of the garage. got to the highway (about 4 miles), set the cruize at 65mph, the road is pretty much flat.

    after 10 miles on the highway noticed the cons mpg is reading 46.5 mpg ehh not good but I'll live with it. the first town I come to is small, the speed drops to 55 mph then 45 and finally 35 with a stop light. light turns green and off I go. stair stepping back up to 65mph.

    now here is the reason for the posting. 3 miles after regaining 65 mph I look at the cons mpg and it is up to 49.5 mpg and climbing, eventually settling in at 52.7 mpg.

    it isn't the actual numbers that bothers me, it is the 3 mpg jump after the brief stop at a traffic light. did the stop reset some calculation? I could understand a nominal increase after the slow down, but not 3mpg and climbing.

    any thoughts?
     
    #1 priustexasbob, Oct 3, 2010
  2. silverfog

    silverfog New Member

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    The most likely answer is nothing to with the traffic light but that you spent the first 10 miles charging a depleted traction battery.

    I've seen a similar pattern after stopping at a restaurant and leaving the dog in the locked car with a/c running to have lunch. The next few miles, mpg shows a hit as it replenishes the charge.
     
    #2 silverfog, Oct 3, 2010
  3. fuzzy1

    fuzzy1 Senior Member

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    Did you look at the reading while stopped at the light? A gradual slowdown should have boosted the reading sharply.

    The stop light was at about 10 miles. After a trip meter reset at a cold start, my mpg starts low because of the warmup cycle, then climbs for far more than 10 miles, usually for the entire trip.
     
    #3 fuzzy1, Oct 3, 2010
  4. Skoorbmax

    Skoorbmax Senior Member

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    I'm sure your avg was fine; it was real due to the charging mentioned above or the long slow down or whatever. Also when car warms up it's bad on gas. 3 mpg increase after 10 min is to be expected, if not more (like even 5-10+).
     
    #4 Skoorbmax, Oct 4, 2010
  5. TheSpoils

    TheSpoils Member

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    Let us know the MPG numbers at the end of your tank
     
    #5 TheSpoils, Oct 4, 2010
  6. priustexasbob

    priustexasbob Member

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    thanks for the replys.

    I guess a bit more info; the town with the traffic light was 30 miles from home and after the speed change there is a down hill run into the town, about 150-200 feet elevation change.

    yes, I looked at the reading while at the light and it was 47.1 mpg. humm, recharging the traction battery, I'll have to keep that in mind.

    again, thanks for the input
    bob
     
    #6 priustexasbob, Oct 4, 2010
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