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Discussion Starter · #1 ·
My privious posting was:

"Could Toyota keep Prius Hot"
Since the first 5, 10 and 15 minutes are crucial in the mpg count, Toyota could improve the heating time of engine, if that is the real case. I say that because when you drive the Prius for an hour and you turn the engine off and you turn if back on right after, the mpg count shows low mpg's again the first 5, 10 and 15 minutes again. Maybe the Prius has the faster cooling system of any car in the market and nobody knows about it.
Then, if it is true that the Prius works better when is hot, why Toyota cool it down that fast, limiting the Prius's usage for long trips. There are a lot people in US and the WORLD that stop and go many times as a part of working and/or shopping manuvers in the city where Toyota claims to have better mpg and where the contamination is grater. I hope Toyota redifine this part of the design in the next 2006 version.


As result of it, I was fired that much, that my computer screen gets burn almost.

The objective of my posting was, and still it is, to search and find the true of that matter, "THE HEAT BEHAVIOR IN THE PRIUS", instead I received the "THE HEAT OF THE MAJORITY OF PRIUS OWNERS". That is why I named this posting, "Prius Owners are Hotter than Prius Itself...!!!".

The heat of Prius owners can not be used to keep the engine hot....!!!!
The heat of Prius onwers can not be used to tell the computer that the Prius is already hot and behave accordinly....!!!

As a painfull result, no contribution was made by Prius Gurus.

In my next posting, I will provide statistics that will demostrate the real Prius mpg.

SEE YA NEXT.....
 

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I think Sanny is hot. :wink:
 

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Ok, look. Your argument is a bit odd. First, most cars don't have a trip computer let alone one that shows 5 min intervals. Also, when they mean city driving, they mean continuous stop and go traffic rather than stop as in shut off the engine. Any car that is run for 5 mins, then shut off, then 5 mins, then off will get much much poorer fuel economy. Perhaps in your case, it's unavoidable so then in your case, any vehicle will suffer - It's just that those vehicles don't tell you immediately.

I assume you know that an engine takes time to get up to operating temperature. Also, ambient air temperature will dictate how fast it will cool down. Toyota already has implemented the thermos. The next best thing is you getting an engine block heater.
 

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Tideland Prius said:
Ok, look. Your argument is a bit odd. First, most cars don't have a trip computer let alone one that shows 5 min intervals. Also, when they mean city driving, they mean continuous stop and go traffic rather than stop as in shut off the engine. Any car that is run for 5 mins, then shut off, then 5 mins, then off will get much much poorer fuel economy. Perhaps in your case, it's unavoidable so then in your case, any vehicle will suffer - It's just that those vehicles don't tell you immediately.

I assume you know that an engine takes time to get up to operating temperature. Also, ambient air temperature will dictate how fast it will cool down. Toyota already has implemented the thermos. The next best thing is you getting an engine block heater.
I have the thermos and the block heater. And still agree with the original posting. That is, the behavior he explains is what I witness as well.
 

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Discussion Starter · #8 ·
15 minutes exclusion

The report I will give you will be in the basis of:

1.- Normal driving in a city like New York City going local and highway.

2.- With and without Prius Magic Pedal Touch.

3.- Figures at 5 minutes intervals.

4.- Average of mathematical calculations discriminating random intervals.

5.- Introduction the following variables:

a) Car Weight and Cargo,

b) Inclination,

c) Tire Preassure, and,

d) Accessories Energy

The elements and methods of investigation will produce numbers that we have not observed yet.
 

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Go ahead an investigate. Change variables. Document your mileage. Modify tire pressure. Alternate driving styles. upgrade your gas octane. Polish with an uber-wax.

Who really cares? I don't. I've never had below 45mpg on a tank, and I'm not one of those who drives the thing staring at the energy consumption screen, like it's a video-game.

Six to ten more miles on the gallon doesn't mean a whole lot to me. And I'm not fanatical, defensive, or crusader-like enough to launch a full-fledged investigation into the Prius' "true" mpg.
 

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Tideland Prius said:
Also, when they mean city driving, they mean continuous stop and go traffic rather than stop as in shut off the engine.
Actually, doesn't EPA's city test include parking stops where the car is off for a time?
 

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But the EPA course is FLAT. I think that's the key. The folks that consistently report very good mileage on this board live where the terrain is dominantly fairly flat. Not necessarily total pancake, but not where the land is geographically young.

It's the long steady grades that get you if you live in a moutain and valley area. You do great when you drive downhill for 40 minutes, but you can only store so much of that, and when it is time to go uphill for 40 minutes, you pay. Especially if you must do so at 70 mph because that's what the rest of the traffic is doing. Likewise with stop and go on hills. You only reclaim so much of the energy and then you have to eat the uphill accelerations, which will put you in the single digits even if you accelerate rather gently.

Perhaps the car should have different settings for different driving conditions; I can see where going deeper into the battery than the car tends to (I'm very rarely below the half point, but not infrequently hitting the green) in hillier conditions would be more efficient because you are likely to recharge the battery with a downhill coast soon. On the flat you are more likely to have to make that up with the gas engine anyway.
 

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DanMan32 said:
Tideland Prius said:
Also, when they mean city driving, they mean continuous stop and go traffic rather than stop as in shut off the engine.
Actually, doesn't EPA's city test include parking stops where the car is off for a time?
The EPA city test is done in a lab on a dynometer. There isn't much time in the test cycle for a "cool down":
http://www.epa.gov/otaq/emisslab/methods/ftpdds.gif

You can view more of the test procedures here:
http://www.epa.gov/otaq/labda.htm

The brief description of the tests are given here:
http://www.fueleconomy.gov/feg/info.shtml#estimates
 

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All right. Now I think mrv is hot.
 

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rmarchena,

With all due respect, no matter what kind of data you are able to come up with, there is nothing that you, as an enduser, can do to change the operating programming of the car. Like a lot of things, even if you were able to best Toyota at their own game, there would be tradeoffs. I can easily imaging that if the parameters that the vehicle operates under were adjusted that economy could potentially be boosted, however at the cost of what? Emissions? Driveability? Engine, drivetrain or entire vehicle life?

After I took delivery of my Prius, I got into a friendly conversation with the dealer. He had sold one to an engineer at one of the local Public Utility Districts (i.e. publicly held electric companies that have really inexpensive power, how's 3.4 cents a KwH or less sound to you). Anyway this guy is basically an electrical engineer. He decided to hook up his computer to the car, and a bit later, after some bad hookups and a couple of data pushes, the car wouldn't drive more than 30 mph. I don't know any details regarding what the engineer was trying to do, however whatever he did didn't do much good for his car.

So, the disclaimer regarding the Prius should really be No user serviceable programming inside.
 
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