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Help in getting the best gas mileage any suggestions?

Discussion in 'Gen 2 Prius Fuel Economy' started by JanTheMan, Jun 7, 2008.

  1. JanTheMan

    JanTheMan New Member

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    2007 Prius
    I recently rented a 2008 Prius fully loaded before making the final decision to buy one. I filled the tank to the brim, then took a ride doing 71mph on the highway. I did a roundtrip of 82 miles, had everything on in the car, air conditioning, radio and the monitor which shows how the car is running. I then filled it back up to the brim, took out my calculator, did the division and got 47mpg. Then I did all city driving at night, lights on, radio on, air conditioning on, stop n go and idling. I filled it back up, took out my calculator and got 46.4mpg.

    This made me a believer of the reports I was hearing and returned the rental car,being convinced of the gas mileage the car got, I then went to the showroom and they had a used 2007 Prius with 11,400 miles on it, I traded in my 2007 Honda Civic and bought the 2007 Prius. I then took the car on the same exact trip, same conditions, and only got 42 mpg on the highway. I filled it up and then did city driving only, everything running in the car, stop n go..idling and only got 34mpg.

    My question is: What could be wrong that I am getting such a difference in gas mileage under the same conditions between the 2 cars? If anyone could give me any information on why this would happen, please let me know as I am very disappointed in the car that I purchased.:confused:
     
  2. ZC1

    ZC1 Junior Prius Owner

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    Same tire pressure as the rental? (you probably didn't check it). Try 40psi front, 38psi rear.

    Anyways, you can get 47mpg and 46.4 mpg easily, so hold off on the disappointment.
    Something obviously is not the same, besides the car, so just check the tire air pressure and redo your trip under the same time period (night?).
    Watch out for a heavy foot on the accelerator.

    ZC1
     
  3. Bill Merchant

    Bill Merchant absit invidia

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    :welcome: Welcome to PriusChat, Jan!
    There are several threads here on how to get better milage, even a whole forum for Fuel Economy. One thing you'll find as you read is that calculating fuel use as you did is notoriously unreliable. The rubber bladder in the Prius gas tank throws too much variability into single-fill calculations, though mpg calculations over several tanks are accurate. The mpg displayed on the screen is usually accurate and also usually slightly (1 or 2 mpg) optimistic.

    One thing to check is your wheel alignment. Maybe the dealer will even give you a free one if you tell him you think your fuel economy is too low. If anything, I'd expect your lightly used 2007 to get slightly better mpg and a new 2008, just because it's more broken in.
     
  4. JanTheMan

    JanTheMan New Member

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    Ok, I will got out and check the tire pressure, and run the car down to near empty before filling up, and do the mpg average then. I am an old dog, and so use to doing it with a calculator to get the average mpg on a car. I will bring the car back to the dealership tomorrow, and make sure that everything is ok with the car. The MFD does fluctuate in showing the mpg as I am driving, of course going down a hill, it shows 99.9, on a small incline it will change, on a flat surface it will change, so I know that it is working. This is all new to me, and I am very light on the pedal, as I noticed that the slightest touch of the pedal makes a big difference. I am LEARNING. I just checked the tire pressure 36LF..35RF...37LF...36RR..I will put in 40 in the front and 38 in the rear, and see what we get.
     
  5. JanTheMan

    JanTheMan New Member

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    Just checked my owners manual, and the manual suggests for 15/16 tires that the pressure should be 35 front and 33 rear. Being that I live in Las Vegas where it gets very hot in the summer months, do you recommend putting 40psi in the front and 38psi in the rear tires?. How much does a tire expand in extreme heat? I will put in the 40/38 as everyone has suggested.
     
  6. 08Prius

    08Prius New Member

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    1. Did you have your oil change? (5W-40 Fully synthentic oil is what you need change)
    2. Did you check your air filter? (clean it or replace it)
    3. Did you set all tires to 45 PSI?

    MY USEFUL TIPS (FOLLOW THESE TIPS BEFORE GOING TO A DEALER)

    THESE ARE MY DRIVING TIPS AND I AWAYS KEEP MY EYE TO IT :
    1. SET ALL TIRES TO 45 PSI
    2. SET AC TO LOW AND ABOVE 72 FF (OFF YOUR AC MIGHT HELP YOU A LOT AS WELL)
    3. ALWAY FILL HALF A TANK OF GAS
    4. CLEAN YOUR AIR FILTER BY AIR BLOW IF YOU PLAN TO GO ON A LONG TRIP (REPLACE IT IF IT GETS DIRTY)
    5. GO BETWEEN 60-69 MPH ( I ONLY DRIVE ABOUT 65 THE MOST SO THAT'S WHAT I GOT MORE MPG)
    6. RELEASE GAS PENAL WHENEVER YOU SEE A SLOW TRAFFIC IN FRONT OF YOU ( I SAVE ALOT OF GAS ON THIS # 6 TIP)


    This image has been scaled down to fit your computer screen. Click on it to show it in the original size.​
    [​IMG]

    * SOME OF PRIUS OWNERS MIGHT FIND THESE TIPS USEFUL AND SOME ARE NOT. SO I AM JUST GIVING MY TIPS TO YOU GUYS AND JUST WANT EVERY BODY TO SAVE MORE MONEY ON GAS.
    IF YOU DON'T THINK IT IS USEFUL THEN PLEASE IGNORE IT.
     
  7. JanTheMan

    JanTheMan New Member

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    I would like to thank everyone for their help and suggestions, I added the correct tire pressure, brought the car back to the dealership and everything is good. I am now getting 44.5 city driving.
     
  8. JanTheMan

    JanTheMan New Member

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    I have another question, when I rented the Prius, I noticed the ride was very smooth and caparable to a full size car, ex...it rode like my Mercury Marquis LS. When I purchased the used PRIUS, I noticed immediately the difference in the ride of my car and the rental car. What is different in the suspension of the standard Prius and the Touring Prius options? Is it just the shocks and tires? or something else to the suspension?
     
  9. Fuzzy

    Fuzzy Junior Member

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    JTM, I'm no expert, just an owner of a 2007 (basic) we bought new and have put 35,000 miles on. I've noticed as the tires have worn (we're about due for new ones), the ride has gotten noisier - I assume tires have a lot to do with the difference. Also, I have to suggest that ride and road noise are pretty subjective. If I'm feeling grumpy, my ride seems noisier and less smooth. Even whether the car is clean or dirty seems to make a difference in how it feels. It really is subjective. Not suggesting you're a grump, though. :) In reply to your economy question, we've averaged an honest 52 mpg over our 35,000 miles. Enjoy your '07. We love ours.