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Put air in all tires a week ago, and now all tires are low in air again. Problems?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Jane Doe, Sep 11, 2018.

  1. Jane Doe

    Jane Doe New Member

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    Hello all,
    About a week ago I got the warning light that my tire pressure was low. I checked the tires and all of them were low ( I believe, I can't remember exactly). I put air in them and then the warning light went away. About a week later the tire pressure light came on again. I checked all the tires using a gauge and all of them were low. I then put air in all the tires and the warning light went away.

    Does anyone know a possible reason for needing to put air in tires again after putting air in just a week before?
    I don't understand how all the tires could have leaks in them. But I am open to any suggestions or ideas about why this happened.

    Thanks!
     
  2. RobertK

    RobertK Member

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    Changes in temperature can cause air pressure in tires to change. You also need to reset the TPMS system using the button under the steering column after adjusting the tire pressure.
     
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  3. ChapmanF

    ChapmanF Senior Member

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    All of mine read low this week, after the substantial temperature drop here relative to last week.

    Pressing the TPMS button under the dash is only needed if you want to change what pressure the warning is set for. If it is set where you want it and the tires are low, you just put air in the tires.

    -Chap
     
  4. bisco

    bisco cookie crumbler

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    pump them up to 42/40 like many of us do. you won't have to add air when the temp changes, and you won't have to adjust the tpms. and the light won't come on unless you have a leak
    i've been doing it for 14 years without issue.
     
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  5. VFerdman

    VFerdman Senior Member

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    If you live in Amherst, MA, I live very close to you and I had the same thing happen yesterday. Suddenly all tires are down to low 30's. It is the temperature change in the area that most likely caused it. It was ridiculously hot last week and now it's in the 60's. This is normal, don't panic.
     
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  6. AzWxGuy

    AzWxGuy Weather Guy

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    You also might want to check the valve cores to make sure they are all tight. And while you're at it, check the pressure in the spare. Sure wish it would cool off here.
     
  7. Salamander_King

    Salamander_King Senior Member

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    Tire pressure fluctuation of 3-4 psi due to ambient temp is common, but without knowing what temperature changes and tire pressure before and after, it is hard to guess what caused the drop. Have you had tire installed recently? If not, any possibility of vandalism? If you continue to have problem, one of those external TPMS may gives you better idea when and how much each tire is losing air. Costs only ~$50 at Amazon.

    IMG_20180830_175002.jpg
     
    #7 Salamander_King, Sep 12, 2018
    Last edited: Sep 12, 2018
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  8. ChapmanF

    ChapmanF Senior Member

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    Plug in a laptop with Techstream and you can also see all four pressures, temperatures, and transmitter battery conditions. Doesn't make as tidy a package to keep on your dash, but on the upside, it's useful for a lot of other maintenance and repairs.

    -Chap
     
  9. Lucifer

    Lucifer Senior Member

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    Tires lose 1-3 lbs a month, and as mentioned, Hugh changes in air pressure accelerate the loss, buy a good air gauge, not a 10dollar sucker and some sort of pump, or buy air, but check them monthly and keep them at 40lbs, better mpg, safer, and easy to spot a low tire, and get an air valve tool to make sure the valves are tight, they usually are, but a bubble every day adds up.(a drop of oil in the valve will show a leak, and if the oil happens to get in, good, lubrication).