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getting 21mpg

Discussion in 'Gen 2 Prius Fuel Economy' started by misterdean, Jan 10, 2017.

  1. fuzzy1

    fuzzy1 Senior Member

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    Typo, and too late to edit. That should read:

    ... 45 is the EPA rating for your year, so that is normal. ...
     
    #61 fuzzy1, Apr 2, 2017
    Last edited: Apr 2, 2017
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  2. srellim234

    srellim234 Senior Member

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    Plus, real-life reporting of the 2006 at fuelly.com shows an average of 44.0 mpg. The six 2006 Prii still being reported at fueleconomy.gov are showing 42.4, 45.7, 41.0, 54.0, 44.0 and 45.7. Over 50 is being achieved occasionally but it is definitely not the norm.
     
  3. jerrymildred

    jerrymildred Senior Member

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    For a Gen 2 to run on electric only requires some pretty specific and gentle conditions. Very light throttle pressure. Speed under 32 mph, if I remember it exactly.

    It can be tricked into EV mode, if you're going slowly on level ground (or a little downhill) by letting off the accelerator completely and then pressing it very lightly. But you won't go far, probably a mile at best, and then the engine will have to charge it back up, so there's actually a net loss doing that since there are heat losses in charging and discharging the traction battery.

    European gen 2 models have an EV button. It can be installed in a North American model, but serves little purpose other than maybe moving it around a parking lot without having to start the engine. But even then, you have to hit the EV button within about 7 seconds of starting the car or the engine will start anyway and run through its first phase of warmup. Gen 3 Prii are a little more robust when it comes to electric only, but you really need a PiP or a Prime to make EV driving a significant part of your drive. On a gen 2, the electric part is mostly a helper. It sort of absorbs, stores, and reapplies energy like a great big spring.
     
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  4. Kishore

    Kishore Junior Member

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    When I bought my used car, 12v battery replacement since readings were lower than norm (w yellow Optima) and air filter (which was dirty) change made positive difference in MPG (from 40-43 to 46/47 avg) of course all this depends on road, glide and how much pedal to metal :) Hope readings of 12V are ok- if not it is worth spending $$ to get new one.

    Regards,
    Kishore
     
  5. dolj

    dolj Senior Member

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    This is normal. The Prius' happy place is 6 bars (the top blue bar).
    No, but for the majority of the time it possibly is. But the ICE (internal combustion engine) running is not a problem, because once you're up to speed a significant amount of time the ICE is running it is running at 49 MPG (US) or better (up to 94 MPG (US), but more usually 67 MPG (US)) to balance out the 9 to 19 MPG (US) used when accelerating.
    They do, but not too often. Your other conception is the other way around, these cars are actually primarily a gas engine with electric assist. As jerrymildred explained in his post above, you, as the driver, do not need to be trying to chase it to run on electric power, just let it do what it wants to do, you will get better results. The only modification to your driving, if you don't already do it, is to adopt economical driving techniques, some of which need to be adapted for the Prius, but overall things like anticipation of the road ahead, driving with as little reactionary braking as possible (a technique known as driving without brakes or DWB), etc, work well for Prius driving. A caveat to DWB is to touch the brakes lightly to increase the regenerative load put back in the HV battery. This is a bit of a feel thing in the Gen II as there is no indicators to which you can refer (unlike the Gen III onwards.), unless you have a ScanGauge or Torque app where you can monitor the HV battery current. The only one technique that needs adapting is pulse and glide, because, in the Prius, you adapt it so that it is entirely controlled with the "go" pedal. Finding that sweet spot where none of the motors are driving (so you are in a true coast), can be difficult at first due to the slow refresh rate of the Energy Monitor screen, but once you become accomplished in finding that sweet spot, it becomes second nature and you can do it without reference to the screen (mostly).
     
    #65 dolj, Apr 2, 2017
    Last edited: Apr 3, 2017
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  6. jerrymildred

    jerrymildred Senior Member

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    The best "glide indicator" I can think of on the Gen 2 is the energy screen. Try to make it so there are no arrows going in any direction. But that's about as easy a balancing your puppy on its nose on a beach ball on a small boat. ;) And you can't do it over 42 mph. So what I did was try to keep the instantaneous mpg at 99 while not regenerating. Then you're really freewheeling. Tricky, but you eventually get a feel for it as @dolj said. In reality, a little bit of regen isn't really hurting anything. But after several months of that, I decided it wasn't worth the effort, and just drove the car and let the computer manage things while I avoided doing dumb stuff like hard braking as long as our screwy traffic lights would allow it.
     
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  7. fuzzy1

    fuzzy1 Senior Member

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    That difficulty level is just for the Gen3, where this indication is essentially broken because it does not understand 'close enough'.

    It works quite well in the Gen2, which allows a bit of slop margin and thus understands 'close enough'.
     
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  8. valde3

    valde3 Senior Member

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    But in a Gen 3 you do have the hybrid system indicator. It makes it a lot easier to stay in coast and it will also make it easier to keep the gasoline engine in efficient range when it’s on. So the Gen 3 is lot easier to drive economically using only the factory instruments than Gen 2. In Gen 3 there’s really no reason to look at the arrows.
     
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