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I'm sure this topic has been done to death, but I have a question about my gas mileage, which has always averaged close to 47 MPG. Not bad, but I had hoped for better. Highway or city driving doesn't seem to matter. I have tried to change my driving habits, slower accelerating, etc., all to no avail.

My question centers around how much work should the electric engine be doing when I am starting from a stand-still? On a few occiasions, the electric engine does the whole job of getting me up to 15 or 20 MPH, then the gas engine kicks in. Ususally, it seems that the gas engine is doing most (or all) of the work from 0 to 20 MPH or more. My MPG on most start ups is generally around 10 - 20 until I get up to cruising speed. Clearly, this is hurting mt average.

Any advice or suggestions out there?
 

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Regarding low MPG's

What state are you from? Is it getting colder? Does the ICE run longer when you first start out?Do you run the A/C ,heater ?
I've been averaging 56 MPG since I got my car in July but my commute is
slow usually under 40 mph.I've notice mpg drop if a car is behind me because I tend to keep the speed above rather than to vary for top mpg.Using cruise control keeps your speed constant but doesnt help MPG's on long trips.Also the A/C off helps with an extra 3-5 MPG too!
But it all depends on traffic conditions(going with the flow,stop and go)
It's not difficult to drop the MPG's in this car.

Regards,Ed
 

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:idea: Partial quote from the Prius "Fuel Economy Information" placard (which was on a rear window when your Prius was new):

"Actual Mileage will vary with options, driving conditions, driving habits and vehicle's condition. Results reported to EPA indicate that the majority of vehicles with these estimates will alchieve between

51 and 69 mpg in the city - and between
43 and 59 mpg on the highway"

Few, if any, cars achieve the EPA published mileage/gallon. Actually, in more than a year, I experience 41-45 mpg in town and 49-54 mpg freeway (~65-70 mph). I'm happy since this is more than twice the mileage on our 4-cyl Camry.
 

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2005 Prius. Nearly 11,000 mi. Dividing all gas put into the thing into the lifetime mileage, Ih have averaged 52 mpg. That is all sorts of in town, interstate and country roads.

I don't trust individual tank mpg, either of the mfd or calculated as with such a small tand and with individual gas pump release pressures, any variance can have a large impact on one-tank calculations BUT, my best tanks have been in the low 69s and worst have been in the mid 40s.

Last week I took a trip of 170 miles south and back -- all on interstate with some driving in a very large metropolitan area. The trip mileage was 53 mpg (calculated and mfd reading). Most of the interstated driving was about 2 mph over speed limit and on cruise control.

Oh yes, other factors. In summer, the mpg climbed a bit, maybe 1 or 2 mpg. I also use synthetic oil and am trying to see the difference between Shell and cut-rate gas. I think I get 1 or 2 mpg better on Shell but not yet absolutely sure.
 

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Don't forget that it's not Toyota's "advertised" mileage. The MPG figures are established by EPA, using impossible conditions. I find about a 20% decrease from the EPA figures to be reasonable in about any car. But because the Prius EPA numbers are so high, 20% looks really big. 48 instead of 60 seems a huge difference. But consider if the Camry has EPA figure of 30, and gets 24, that's still 20%.
 

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Please post your location (even if it's just the state) as it's helpful to us to respond accordingly.

Topography is a main factor. Hills will kill mileage. Try to maximise gliding (that's no arrow showing on the MFD). This means your engine's off and you're not using the battery. Also, if it's new, 47mpg is fairly good. Take note of ambient temperature too.
 

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Tideland has hit one of the major things. Brand new Prius will generally not get max mileage. Tires need to get the edges worn off. Then you'll go through the break in with the tires again after the first tire rotation (thanks John, for that reminder to all of us). Warm dry weather generally leads to higher mileage than cold and wet.
 

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Sanny said:
Don't forget that it's not Toyota's "advertised" mileage. The MPG figures are established by EPA, using impossible conditions. I find about a 20% decrease from the EPA figures to be reasonable in about any car. But because the Prius EPA numbers are so high, 20% looks really big. 48 instead of 60 seems a huge difference. But consider if the Camry has EPA figure of 30, and gets 24, that's still 20%.
Sanny articulates the "Tyranny of Large Numbers", a theory which states that similar differences SEEM larger when the numbers are larger.
 

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pbourassa said:
I'm sure this topic has been done to death, but I have a question about my gas mileage, which has always averaged close to 47 MPG.
Yes, in my opinion it has been done to death. Your mileage is better than mine (45mpg) and probably a little better than the average for all Prius owners. It has been apparent for years that EPA estimates drastically overstate the mileage of almost everything. Who ever believes them? Dodge Dakota drivers complain because they get 10mpg rather than 14. Probably 90% of car owners notice mileage lower than what was on the window when they bought the car, but because the Prius is largely identified with the question of fuel economy, disparities are more likely to be broadcast and become grist for the hybrid-skeptic contingent. You are doing fine and there is nothing wrong with your car.
 

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Check tire pressure. I got similar MPG when I first got mine, but then noticed the tires were a bit low. It can make a difference. I average 50 mpg and I live a fairly 'hilly' area - lots of long uphill and downhill stretches, and going 70-75 mph at that (highway of course). When I start seeing between 45-50 mpg, I check the tires....my 2cnts.
 

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Take your car to a indoor dynamotor, and test it under the exact conditions of the EPA and I bet you will get similar results. Car warmed up, standard temp, no wind resistance, etc etc. The EPA figures are standard conditions for purposes of comparison. The numbers only allow you to compare one car with another. Period.
 

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pbourassa said:
I'm sure this topic has been done to death, but I have a question about my gas mileage, which has always averaged close to 47 MPG. Not bad, but I had hoped for better. Highway or city driving doesn't seem to matter. I have tried to change my driving habits, slower accelerating, etc., all to no avail.

My question centers around how much work should the electric engine be doing when I am starting from a stand-still? On a few occiasions, the electric engine does the whole job of getting me up to 15 or 20 MPH, then the gas engine kicks in. Ususally, it seems that the gas engine is doing most (or all) of the work from 0 to 20 MPH or more. My MPG on most start ups is generally around 10 - 20 until I get up to cruising speed. Clearly, this is hurting mt average.

Any advice or suggestions out there?
Well I would have to know where you are at. What the daily temps are? When your area changes from summer formula gas to winter formula? How many miles do you have on the car? How do you drive the car? Have you searched the various web sites and found the best ways to drive the Prius?
 

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pbourassa said:
I'm sure this topic has been done to death, but I have a question about my gas mileage, which has always averaged close to 47 MPG. Not bad, but I had hoped for better. Highway or city driving doesn't seem to matter. I have tried to change my driving habits, slower accelerating, etc., all to no avail.
One year ago, my Prius was 3 months old, with 3886 miles on it on October 23. My average mileage from Oct 1-Oct 22 was 49.5 MPG. Right now, my Prius has been in use for 1 year, 3 months, with 24787 miles on it. My average mileage from Oct 1-Oct 22 this year has been 55.7 MPG.

Others have had good advice. Mine? Don't drive aggressively. It's that simple. When I drive aggressively (even if not 'fast',) I get bad mileage.
 

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I am getting around 50 MPG and that is just fine with me. (In the city, and in South Florida, where it's warm, and flat)...

I sometimes get better. But to be honest, I am just happy to have anything over 30 MPG.
 

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hdrygas said:
Take your car to a indoor dynamotor, and test it under the exact conditions of the EPA and I bet you will get similar results. Car warmed up, standard temp, no wind resistance, etc etc.
"warmed up"???

No. The EPA test is done after over night cooled down.

[email protected]
 

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ken1784 said:
hdrygas said:
Take your car to a indoor dynamotor, and test it under the exact conditions of the EPA and I bet you will get similar results. Car warmed up, standard temp, no wind resistance, etc etc.
"warmed up"???

No. The EPA test is done after over night cooled down.

[email protected]
EPA highway test is done with a warm engine, city test with a cold engine.
http://www.fueleconomy.gov/feg/fe_test_schedules.shtml

Problem is, very few people drive like the tests! (city test is 11 miles, 31 minutes, average speed of 20mph, max speed 56mph, done in 68-86F temperatures, without heater or AC use. highway is done also without heater/AC, 68-86F temperatures, but is 10 miles, 12.5 minutes, average speed of 48mph, max speed of 60mph!)
 

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Don't speed.

Anticipate stops as far in advance as possible, and decelerate smoothly to them (either by braking continuously or by coasting) as much as is practical (some places one can't go under 10 MPH for the last half block without getting shot at).

Quick starts may actually help. The engine is going to run anyway, so you might as well use it at full load, where it is most efficient, until you reach your desired speed.
 

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My mileage has been quite low with the last tank and a half of gas. I'm driving in Brooklyn, NY with a/c or heat on at times. I used to average around 42-45MPG through August, when we first bought the car.

Around mid Sept., I found that the tire pressure was backwards and very low (33/35 front/back -from the dealership), and bumped it up to 40/38 (front /back). Since then, the mileage has seemed to drop around 33MPG or lower, even like 28MPG at times. In NY, I'm not able to drive as patiently as I'd personally like to, but I didn't think I'd see such a large drop. The outside temp. is constantly dropping.
 
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