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Problem with fuel mileage

Discussion in 'Gen 2 Prius Fuel Economy' started by Prostar8.20, Jul 19, 2005.

  1. Prostar8.20

    Prostar8.20 New Member

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    My wife filled up with fuel and went thru the car wash and our Prius is acting up now. We used to get 52 mpg, now it's a struggle to get past 44. The battery seems to be lower than it used to be and the screen shows that the energy coming from the engine to the motor for recharging , blinks on and off. Any ideas? I dread bringing this thing to the dealer, these guys struggle with basic stuff never mind this.
     
  2. efusco

    efusco Moderator Emeritus
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    More info please. Model year, mileage on the ODO, how sure are you of your baseline mpg and how far have you driven seeing the current, lower, mpg? Any change in driver, driving conditions or driving style?

    Is the Multi-display (MFD) actually blinking off and on--ie. shorting out or are you just seeing the color bars on the Energy screen stop and start/flashing back and forth?

    It's not out of the realm of possibility that you got water into the the engine compartment and shorted something out, but I'd expect something a bit more catastrophic and some MILs or something to show up.
     
  3. galaxee

    galaxee mostly benevolent

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    Maybe the battery got very low in charge during the car wash? I noticed when we first got our EV switch that if we ran the battery too low the MPG really, really suffered. That would be a similar situation. The gas engine spends lots of energy recharging the battery and your MPG drops along the way.

    Also, the first 60-80 miles on a new tank is highly variable.

    Also consider that different people have different driving styles... maybe that's part of it? I filled up 2 days ago and turned the car over to my husband while he's working on replacing the fuel pump on his car. I drove it 3 miles from the gas station to home and ended up at 90ish mpg. He took it to work and back, 5 miles each way, and came home with 32 mpg (no wonder i never let him drive my pri!)

    Hope that's somewhat helpful. I'd give it a while before going to the dealer unless something major cropped up.
     
  4. Prostar8.20

    Prostar8.20 New Member

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    Our Prius is an 05 with about 3000 miles on it. The display is fine, the bar that shows charging from the engine to the battery flashes, is that normal? The mileage dropped off abruptly after the car wash/fill up. I also noticed it's hard to get it onto the electric only cycle. This could be our imagination but I don't think so. We're in tune with our little electric/gas friend. Maybe the hot weather, I don't know. Called dealer and they said it was normal, what else can they say, they have no clue as to how to work on these I'm sure. We know about the sensitivity of the mileage when just filling up, this is an ongoing late in the game fuel mileage problem. Thanks for your replies.
     
  5. galaxee

    galaxee mostly benevolent

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    How's the charge on the battery?

    Sometimes in my experience a good long drive will clear these things up.
     
  6. popoff

    popoff New Member

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    <div class='quotetop'>QUOTE(Prostar8.20\";p=\"108754)</div>
    Perhaps you might consider a trip to the dealer and have him check for any spurious codes. As mentioned earlier, if there were a problem it probably would have generated a code which is now stored in the computer.
     
  7. Tideland Prius

    Tideland Prius Moderator of the North
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    Maybe the water was really cold. I noticed that after I washed the car, even though I had the engine warm and everything before I washed it, the next time I start it up, it would act as if I've left it overnight in the middle of winter. i.e. the warmup period is much longer.
     
  8. Prostar8.20

    Prostar8.20 New Member

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    Good news, we're back in the low 50's!! Something was going on and I can't peg it but I think we're back on track. The temps we're up in the high 90's, maybe that had something to do with it. Thanks to all for your assistance.
     
  9. galaxee

    galaxee mostly benevolent

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    Glad to hear it.

    I'm sure it was a battery discharge. In fact, I sent you a private message about it.

    A little driving around charges it right back up.
     
  10. rbs

    rbs New Member

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    Well, here's my story. Rarely - and I mean very rarely - does my beloved Prius drive on electric only around town. I mean that the first 10 feet off a stop sign we're all electric [99mpg] and then, even with the lightest touch on the gas, I'm all gas [15-20mpg]. My best mpg is on the highway where I'm routinely between 47-50+, but then I drive around town and wham!, mpg drops like a stone. And trust me, I'm really compulsive. The battery seems to discharge very quickly so my guess is the engine is running to charge it up. Once - once - in traffic on the freeway the car acted the way I expect it to. All electric in the stop and go even up to 30 mph. It happened briefly this evening, too. And boy oh boy, do I get mpg. But usually my mpg is a big disappointment. Naturally the dealer tells me, "It's just perfect." It isn't. I've driven a friend's Prius on the same route around town and gotten much better mpg on his car than mine. What could it be? What should I do? Help very, very gratefully appreciated. Thanks!
     
  11. efusco

    efusco Moderator Emeritus
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    Let your friend drive your Prius on his usual route, and then your usual route and see if he thinks it behaves any differently than yours.

    I won't discount the possibility that something is wrong, but I seriously doubt it. I suspect that your city driving technique could use some honing that would get you better numbers.