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I'm getting low mpg on my 08 prius :(

Discussion in 'Gen 2 Prius Fuel Economy' started by vasukboopathy, Jul 22, 2008.

  1. vasukboopathy

    vasukboopathy New Member

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    Hi:

    I got my 08 prius 6 months back. It's pkg 6 touring model.

    I have never got more than 41 mpg on average and off late am getting 39-40 mpg :(

    I do not rev the engine much and am soft on the gas pedal. I commute 12 miles on an avg. daily. 8 miles in the city and 4 miles on the highway.
    I live in california so, the weather is good and my tire pressures are around 35. The odometer reading is 2800 miles. I did my first service couple of months back.

    It beats me when people say they get 45-50 mpg. I have tried every trick possible and can't get beyong 41.5.

    Could you let me know how i can work on my mpg numbers ? Should i take my car on a long drive considering the fact that i drive only 10-12 miles a day ? Or is it something else ?

    Thanks much!
     
  2. kazots

    kazots LifesaBeach

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    It is probably the way your driving the car. Use PC there are alot of info on this topic.
    Check your tire pressure a must.
     
  3. TonyPSchaefer

    TonyPSchaefer Your Friendly Moderator
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    :welcome: Welcome to PriusChat, V.
    For the first nine months, I was in the 40s.

    There's nothing wrong with the car, so don't worry about that. There are many different aspects that go into achieving good (or not-so-good) mileage in the Prius. You have opened a can of proverbial worms.

    First of all, there is no other commercially available car for less than $30k that will give you 41mpg. Keep that in mind.
    Secondly, you say that you've tried every trick in the book. My personal preference is to drive the car first. That is, get to know the car. Let the car get to know you. Stop worrying so much about improving your mileage and just enjoy the ride. There are two documented break-in points at which people have reported improvements in their mileage. You're not there yet.

    Lastly, for now, I have said many times that the harder I try the lower my mileage. I honestly believe that it's simply because I'm trying too much.

    I'm sure many people will reply telling you to pump up your tires or focus on pulsing and gliding or something else. But my advice is to chill out for now. It will come.
     
  4. efusco

    efusco Moderator Emeritus
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    2800 miles in 6 mo equals around 15 miles/day on average...you are probably doing mostly very short trips despite your reported commute distance. Short trips are a killer for mpg.

    Look at the stickies on this fuel economy forum and read them carefully. There are a number of things to check including having an alignment check. Being light on the gas can help or hurt you depending upon what, exactly, you mean. The prius runs better with a moderate pressure on the gas then quickly getting off of it completely to let the car glide along (ie pulse & glide).

    What speeds are you running on the highway? Can you slow down. How about following distances and habits as you drive?

    At 2800 miles you've yet to even get your tires broken in adequately.
    Take your Prius out for a weekend drive along some nice sedate country roads with rolling hills and top speeds around 45mph. Keep the AC set to around 76-78 if you need it at all. Don't feel pressured to go faster if someone's behind you, let them pass...don't follow anyone too closely. See that stop sign 1/2 mile ahead? Ease off the gas now and just gently glide in. Reset your mpg before that drive, don't look at the consumption guage/trip mpg until you get home. Betch a wooden nickle you're over 50mpg when you get home.
     
  5. nerfer

    nerfer A young senior member

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    The short commute is definitely part of it.
    You don't need to be too soft on the gas pedal, but you do want to be soft on the brake pedal - anticipate slowdowns, red lights, etc. And keep the speed as low as the traffic will allow. With a short commute like that, it will only cost you a minute of your time. It may surprise you, but you don't want to use your battery more than necessary - it's energy came originally from gasoline after all, and there's loss of efficiency in capturing, storing and releasing that energy. Trying too hard to use the battery system is counterproductive.

    But mostly - pump up the tire pressure. I'd recommend at least 10% over the minimum value posted on the door (35 front/33 rear -> 39/37), many people here run their tires around 42/40 psi, a few 'crazies' much higher than that. Of course, some people feel that you must keep the manufacturer recommended setting, but that number is really a compromise between the engineers and the sales people, between handling (moderately high psi is best), tire life & blowout resistance (higher psi is better, at least to sidewall rating of 44 psi), fuel economy (higher psi is better) and ride comfort (lower psi is generally better). Note that only the ride comfort is improved with lower pressure. Handling is the gray area, and seems to be somewhat subjective in the threads here that cover it. And there's a lot of threads on tire pressure if you want to look into it more. But nothing wrong with adding 10% to the numbers posted on the door frame.
     
  6. nerfer

    nerfer A young senior member

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    The commute was 12 miles for both ways. I had to read that part twice too. 6 miles one way vs. 12 miles one way makes a big difference in overall mpg. But like I've said elsewhere, the important number is gpm - gallons per month. And 41 mpg at 15 miles/day is about 11 gallons/month - not bad at all.
     
  7. a priori

    a priori Canonus Curiosus

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    If Tony suggests that you chill, I will not say otherwise.

    I will add a couple of observations, though.

    The first is that you just don't drive your car very much. Your commute is only 12 miles. Assuming you return home each day, you've put 24 miles on your car. Because your car has just 2800 miles on it after six months, it appears you have driven to work five days a week for six months and haven't taken the car anywhere else -- not a mile out of your commute range and absolutely no where on the weekends.

    Sounds Great!! No one can accuse you of wasting gas. So your gas mileage isn't 50 to 60? You are not wasting any fuel. Imagine what your mileage would be on a car rated in the 20s?

    I don't want to suggest you go driving just to burn fuel and see if you can improve your mileage. I WILL suggest you go driving just to learn more about your car -- and to enjoy it!

    Take a couple of days to drive up the PCH. Enjoy yourself and your great car. I guarantee you the mileage will increase!!

    If you do not see gradual increases during the next few months, then post again and give us more details. My guess is that your A/C is on Auto at 72, and that you are in a position where you are in traffic jambs very soon after startup of the car. With the A/C on, the engine will not turn off as frequently, meaning your MPGs will be less than if you simply rolled down the windows (except at 50+ mph).

    This is nothing to fret about. If you want to increase mileage, you will find a way to do it, and you will develop a valuable knowledge-base in the process. Please share that info with us throughout the process.
     
  8. pewd

    pewd Clarinet Dude

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    i get 50+ from September - May ; during that time I put 75miles a day on, 4 days a week. The 5th day each week its 125 miles.

    During the summer, most of my trips are less than 5 miles, with 3 weekly 50 mile trips. I average closer to 44 or a bit less in the summer. Plus its 100 degrees and the a/c is blasting in the summer. Weeks in the summer when I don't make the 50 mile trips its closer to 35mpg.
    E.G., short trips in high heat with the A/C on full really kill the mileage.

    So - its your short trips. The car just isn't getting warmed up fully. Normal.
     
  9. KandyRedCoi

    KandyRedCoi S is for Super!

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    its the short travel distance of 12miles, and did you do the "standard" set up that help increase MPG???

    anywho i have a 2008 p6 touring as well, and avg about 42mpg combined
     
  10. Ct. Ken V

    Ct. Ken V Active Member

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    Hey, a priori,

    Apparently you didn't look too closely at the math in Evan's post #4 or the confirmation of the original poster's 12 miles TOTAL (round trip) per day stated in nerfer's post #6 before typing your post. That even lower miles travelled than you realized there would certainly have an even more negative effect on getting good mileage #'s.

    Ken (in Bolton,Ct)
     
  11. Highly ImPriused

    Highly ImPriused Impressive Member

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    Why I oughta ...!

    The funny thing is that most of these so-called "crazies" are the safest drivers you'll ever meet. It's a different kinda crazy around here.
     
  12. rwhoyle

    rwhoyle Member

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    My wife and I both drive Tourings and have found 40 psi front/38 psi rear to be a good compromise between good mileage and ride comfort. We both average between 46 and 52 MPG. Try to eliminate your short trips as they are MPG killers and increase your tire pressure. You will notice an immediate positive impact on your mileage.
     
  13. KandyRedCoi

    KandyRedCoi S is for Super!

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    tires set 42/40
    a/c temp no lower than 73deg
    get car aligned by a pro
    cruise control as much as possible
    speed not to exceed 70mph
    my simple set up
     
  14. Sheepdog

    Sheepdog C'Mere Sheepie!

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    cruise control kills my mpg efforts. I tend to do better without it. try the easiest method: Drive while load. This means get a set speed and hold the pedal at that place. when going up or down a hill let the car slow down or speed up just dont move the peddle. I can boost my mpg by multiple numbers that way. I stick to 60 on the interstate and just let the car speed or slow as it wants. I get 50-53 regularly
     
  15. N3FOL

    N3FOL Member

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    Low 40's on a 12 mile one way commute is low in my books. As suggested, pump up your tire pressure to at least 40 psi in front tires and 38 on the rear tires. Drive the Prius like a normal car and as smooth as possible. Hope your mpg will improve a bit.
     
  16. F8L

    F8L Protecting Habitat & AG Lands

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    What it all boils down to is if you are only driving 12miles per day then don't worry about it. You're not spending much on gas nor are you adding a ton of emissions to the air. Granted you could do much better with an EV or riding a bicycle to work but that is for another thread. :)

    Relax and enjoy the car and know that any other car would get subpar fuel milage without a proper warmup cycle as well. IE, you cannot acurrately compare the high-side EPA ratings on a Yaris with the milage you are getting on your Prius as the Yaris would suffer as well.
     
  17. vasukboopathy

    vasukboopathy New Member

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    Hey guys,

    Wow ! I honestly did not expect such detailed explanations and tips :) Thanks much.

    I did not wish to open a can of worms with my post actually. My apologies if it did. I must admit i'm a very satisfied prius owner. It's just that i was concerned if my car was getting tuned the wrong way :)

    On the miles i drive every day, I meant 6 miles one way and 12 miles round trip. Here is the break up for the 6 mile route:
    first 3 miles in the city - maybe around 7-8 traffic lights ie; a light every 0.4m
    next 2 miles on the highway at 65 mph
    next 1 mile in the city - around 2 traffic lights.

    As someone pointed out, i think it's just the case of my car not getting warmed up enough. Anyways, i'll take your suggestion and just chill for the moment :) I'll keep you guys posted on my mpgs as days pass along.

    One question, what is the normal break in period for prius in terms of months or miles ?

    Thanks once again for all your replies.
     
  18. bmg21

    bmg21 New Member

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    It is tough to see large numbers in MPG's with a 6 mile commute. I bought a scangauge and really noticed an improvement considering you can tell when you can get to stage 4 operation in the car and when your driving with load. And more than likely, you could with those first set of stop lights. When you get on the highway, try going 55, and do it manually or 60 if you have too. Try and get in some super highway mode and hold it. The next two stoplights, you should be able to almost glide, or pulse glide and that mile or so should be 100mpg. Pump up the tires and see how you do.

    b
     
  19. ranchogirl

    ranchogirl New Member

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    Mine is low too. I put around 40 miles a day on my car. It has about 600 miles on the car so far, and I'm averaging around 36. It was around 33 in my first tank, so it's improving, and the car is new, but still.

    I think I may have dh check the tire pressure. He also has a Prius that he drives HARD, and he gets around 42.
     
  20. jazzpsy

    jazzpsy Junior Member

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    Good news from here. It galled me thtat every other Prius driver would tell me that they were getting at least 8- 10 MPG more than my 2004 P. (Upper 30's vs. mid 40's to low 50's.) I solved the problem: driving (for me) fanatically slow - speed limit up to 55 MPH and setting cruise control at 61 MPH on 65 MPH highways. So I am driving 10 - 15 + MPH slower with the result that my MPG has increased 25%+. Now i can brag - 50 MPH! Not bad for where I live - pretty hilly.