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Gas Mileage Went Down 11 MPG

Discussion in 'Gen 4 Prius Fuel Economy' started by Coast Cruiser, Dec 2, 2016.

  1. Dragon Rider

    Dragon Rider Active Member

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    Sorry, I drive 90 miles round trip everyday.

    Posted via the PriusChat mobile app.
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    Just a brain bubble going on?
     
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  3. ATHiker

    ATHiker Senior Member

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    I wager that you made a swing through the drive through this morning for a cup of coffee. Am I right?
     
  4. Dragon Rider

    Dragon Rider Active Member

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    Not really . It a long trip everyday. I had a Ford 150 a full tank was like 80.00 dolllar. Glad I found the Prius.

    Posted via the PriusChat mobile app.
     
  5. ATHiker

    ATHiker Senior Member

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    Your screen shot indicated it took you an hour and 12 minutes to travel just 35.5 miles.

    That's an average speed of 30 mph, not 60 to 65 mph.

    If you didn't take a detour to a drive through, perhaps you stopped for a short nap and left the engine running?
     
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  6. Dragon Rider

    Dragon Rider Active Member

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    This is why I ask how 30 mph came up . Maybe you counting the traffic light which today I got almost all green . I was really surprised about not getting too many red light. I did not stop at all for coffee. Something is not right ?

    Posted via the PriusChat mobile app.
     
  7. bisco

    bisco cookie crumbler

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    the mph average on my car always seems low because it counts time sitting at kites and stop signs, etc. most od my driving is local at 30-40 mph, but average is always 18-22.
     
  8. Prodigyplace

    Prodigyplace Senior Member

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    kites??
     
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  9. bisco

    bisco cookie crumbler

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    never pass a kite without stopping.;)
     
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  10. RCO

    RCO Senior Member

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    Get indoors man! You're gonna freeze ya butt off!!:ROFLMAO::ROFLMAO::ROFLMAO:
     
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  11. Welco

    Welco New Member

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    Cooler weather also effects tire pressure. Check them. I run at 42psi and get great mpg.

    Posted via the PriusChat mobile app.
     
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  12. Cap'n Steve

    Cap'n Steve Junior Member

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    Listen to you people. I can't get over 36mpg no matter how gentle I drive in eco mode. Im at like 37 hwy, 29 city. And nobody can tell me why.

    Posted via the PriusChat mobile app.
     
  13. Prodigyplace

    Prodigyplace Senior Member

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    There were many fuel efficiency improvements in Gen 4 starting in 2016. Your 2010 would be an early Gen 3 model. Perhaps some people with the older models have some tips. I am a relatively new Prius driver, myself.

    You may want to post your question in the Gen 3 Fuel Economy forum too. Gen 3 Prius Fuel Economy | PriusChat
     
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  14. Mendel Leisk

    Mendel Leisk Senior Member

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    Where (more specific than "US") are you located?
    How many miles on the car?
    Had it since new?
    Any notable problems?
    How long are your typical drives?
    12 volt battery ok?
    Tire pressures ok?
    Brakes inspected?

    Maybe copy and paste this questionnaire, answer the questions, too:

    Fuel economy complaints/queries? Please copy, paste & answer these questions, esp. if you're new | PriusChat

    Our lifetime mileage is 4.9 liters/100 km, which translates to 48 mpg. We have a 2010 with the 17" rims, do a fair number of short grocery runs, and some across town. Both my wife and I are driving it, sort of trying, abide by speed limits, drive strategically, but not trying hard.

    Edit: see from your other postings there's some codes, the car has 184K miles, you're not first owner. Not sure, but for sure something's seriously pulling your mpg down. Get the codes checked first?
     
    #34 Mendel Leisk, Dec 3, 2016
    Last edited: Dec 3, 2016
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  15. Cap'n Steve

    Cap'n Steve Junior Member

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    Thanks for the extensive reply to my comment. Ive only had it a few months now. 190k miles. It was getting about 43hwy when i got it. Ive been chasing multuple codes on this car. From head gasket leak, to weak 12v, to hybrid system, to intake leak, to misfire. Been a nightmare really. I can't decide whether to dump this car and try again....or actually bring it to a good shop and try ti exercise the demons. I bought a battery cell and took out the hybrid battery. But all cells tested 7.3 or better. So no replacement. Did replace the 12v tho. Which has pretty well stopped the hybrid system warning. The gasket leak is held at bay right now with KStop in the coolant. Gees....

    Posted via the PriusChat mobile app.
     
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  16. Raytheeagle

    Raytheeagle Senior Member

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    What work has been performed since you have owned it on the intake side of the ICE? Has the PCV valve been changed? You said you have misfire codes, was one of them P0401 which is for the egr valve (there is a TSB for that)? Has the egr valve been pulled? What about the intake manifold, has that been cleaned? Does the car consume oil? Any service records from the previous owner? When were the spark plugs changed?

    While you say this has been a nightmare, any car with over 180 k miles will have issues. The good thing is this is a large forum with a lot of active members who are more than willing to help, if you help us by answering some questions:).

    Keep us posted(y)
     
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  17. eman08

    eman08 Active Member

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    I'm getting around 30-40 MPGs around this time as I live in the Midwest. Just a few months back I was getting 50-58 MPG calculated by hand. This is in a 2nd gen Prius.

    Posted via the PriusChat mobile app.
     
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  18. Raytheeagle

    Raytheeagle Senior Member

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    As a Gen III owner since 2009 and with 145 k miles and counting on out 2010 Prius II my lifetime mpg in the car is around 48-49 mpg. I have lived in 3 different states with different driving conditions, but I began to see a decline in mpg late last year (dipped to around 43 mpg). I read in the Gen III forums about others with similar issues and investigated the egr and intake systems. This was the source of my issues:).

    Mpg has now gone back up to around 50 mpg with relatively flat terrain and traveling at 70mph. Just did an 850 mile round trip where the average speed was 75 mph and the mpg dropped to 42. But that was expected :(.
     
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  19. Cap'n Steve

    Cap'n Steve Junior Member

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    I dont want to hijack another guys thread (he says after already doing so). So ill start a new thread and include all of those pertinent Q&As. Maybe i can salvage this thing if i take a breath and try again with support from the forum. You guys are pretty awesome. I hope to help others on here if I get to the other side of my problems, having learned a lot.

    We did take out the injectors and replace the orings. One was torn which was causing the misfire code. I think now, the intake leak is due to putting everything back together poorly....maybe.

    Posted via the PriusChat mobile app.
     
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  20. Coast Cruiser

    Coast Cruiser Senior Member

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    No problem. Post away! Full speed ahead. I don't have a problem with threads jumping around to different subjects. And sorry to hear about all the problems with your Prius.