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Cold temperature causes tire to deflate?

Discussion in 'Prius c Technical Discussion' started by ECOMan, Jan 11, 2013.

  1. ECOMan

    ECOMan Junior Member

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    Hey guys, do cold weathers cause tires to deflate?

    On my way to school today I noticed the tire pressure light. I've had the car only for 3-4 weeks. Never had any issues with it.

    The weather was around 45degrees
     
  2. usbseawolf2000

    usbseawolf2000 HSD PhD

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    Every 10 deg F drop lowers about 1 psi.
     
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  3. john1701a

    john1701a Prius Guru

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    That means they are 25% below the minimum... the danger zone. Add air at your soonest convenience!

    Higher PSI equates to better efficiency and less tire wear anyway. Some people stick with the automaker's "best tradeoff" recommendation. Others choose close to or at the tiremaker's cold pressure maximum.
     
  4. ECOMan

    ECOMan Junior Member

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    Thanks guys.

    Problem Fixed for now.
     
  5. xs650

    xs650 Senior Member

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    You should get a good gauge and check your tire pressures at least monthly. You should check them in the morning before your drive the car which warms the tires up.

    One usually unmentioned reason for running higher than sticker tire pressures, such as 42/40 is that you can lose more pressure before handling and tire wear take a big hit.

    Don't trust any dealer or shop to inflate you tires to the right pressure, always check them yourself with a good gauge as soon as practical.
     
  6. RocMills

    RocMills Active Member

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    I've wondered myself about this... I had my tires inflated to 42PSI just before winter struck, and when I checked them last weekend they were all back down to 35 (which might help to explain my decrease in MPGs lately). Have a lengthy (and the first for this car) road trip planned in a few weeks, so want everything in tip-top shape before I leave.
     
  7. F8L

    F8L Protecting Habitat & AG Lands

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    Here you go. :)

    image.jpg

    Tire Tech Information - Air Pressure, Temperature Fluctuations

     
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  8. Mendel Leisk

    Mendel Leisk Senior Member

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    Yes, get a simple stick gauge for beginners, and get used to it. I've got a few, got another recently when I couldn't find one, and dang if I could get it to seat properly. Found the old one again, and no problems.

    Check pressure when the tires are cold, and try to add air when you've only driven a mile or two. If you have to add air to tires after extensive driving, overshoot a little, and check them again when they're cold.
     
  9. dhanson865

    dhanson865 Expert and Devil's advocate

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    I don't agree with the 1 month part. My Yokohama AVID ENVigor didn't lose any air the first 6 months (I manually changed the pressure after that from 48 to 51 or some simialar change up near my sidewall max of 51).

    I'm sure with older tires, especially with dry rot invovled, that rule might apply but with a proper setup on good tires you might not see any air lost due to time.
     
  10. dhanson865

    dhanson865 Expert and Devil's advocate

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    In my case they were 185/65/15 just like all Gen II stock tires. They were higher quality than the OEM and most cheaper tirees but not larger.
     
  11. ursle

    ursle Gas miser

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    If just one tire was lower I'd suspect the valve stem, I'd get a valve stem tool and check tightness, then I'd drip some oil on the valve and check for leaks
    Yes tires lose air every minute of every day, so get a good air pressure gauge
     
  12. F8L

    F8L Protecting Habitat & AG Lands

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    It's just an old rule of thumb. I agree it doesn't seem to apply much anymore.

    As for the new troll. Don't quote it. Just ignore it. It's been reported.
     
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  13. ECOMan

    ECOMan Junior Member

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    I guess the problem is not fixed because the tire pressure light has been going off daily. The temperature has been extremely cold lately in SoCal. This is rather unusual.

    It's funny though. The tire pressure light is going off only for one specific tire(rear drivers side).

    It could be one of two things. I have a hole in my tire or the cold weather is the caused of it.
     
  14. F8L

    F8L Protecting Habitat & AG Lands

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    Are you setting it correctly? You have to set it at the coldest part of the day and not inside an insulated garage.
     
  15. xs650

    xs650 Senior Member

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    It is most likely a slow leak. A tire shop should be able to find it. I doubt that SoCl weather would be cold enough to cause a problem other than the standard rule of thumb 1 psi per 10 degrees F pressure drop.

    Modern tires can have screw or nail in them and leak as slow as a couple PSI per week.
     
  16. ursle

    ursle Gas miser

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    So, did you check for a leak at the valve stem?
    You could take off the wheel and find something large enough to submerge it in "water" upright or better yet vertically, follow the bubbles
     
  17. ursle

    ursle Gas miser

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    Wondering, what troll?
    Reported for what?
    Was a post deleted?
     
  18. F8L

    F8L Protecting Habitat & AG Lands

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    You can use a spray bottle filled with soapy water to find air leaks too.
     
  19. ECOMan

    ECOMan Junior Member

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    I will bring my car out to the tire shop in a day or two. The weather in SoCal was 33 degrees last night. Might be a factor
     
  20. F8L

    F8L Protecting Habitat & AG Lands

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    It shouldn't be a factor if you aired them up correctly. If you did then you hace a leak or faulty TPMS.