Flat tire at 70 psi?

Discussion in 'Gen 3 Prius Main Forum' started by Peter1, Jun 28, 2025 at 7:17 PM.

  1. Peter1

    Peter1 Junior Member

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    I saw on of my Prius tires fairly low, so I put my handy dandy P737DCN 18v Power Inflator on it. fluctuated wildly between 40 - 70 psi. I tried it again a few days later - same thing. And again the next day. The other tires look normal. What's going on?
     
  2. Tombukt2

    Tombukt2 Senior Member

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    You talking about the gauge on the machine I no use or read that until I stop pump . Schrader maybe sticking gunned up from slime like antics!?
     
  3. bisco

    bisco cookie crumbler

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    check it with a tyre gauge
     
  4. Stevewoods

    Stevewoods Senior Member

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    Your Ryobi is a fairly O.K. tool, but in my experience, most of the $50 and under inflators are somewhat questionable as to measuring actual PSI in tire.

    Also, your question is not really clear. Not sure what you are asking. Tire goes low after a day? Could be loose valve stem or could be a tire leak.

    If pressure drops everyday....something is wrong.

    Sometimes just tough to get an accurate tire PSI READING from the small compressors.

    Stop by a tire store, ask them to check pressure.
     
  5. ASRDogman

    ASRDogman Senior Member

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    ??? What is "fluctuated wildly"???? The inflator, or pressure in the tire???
    You likely have a nail in the tire if it goes down overnight. Should be easy to see.
    Then plug it. After removing the item in the tire of course.

     
  6. Grit

    Grit Senior Member

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    70?! You must be getting 70mpg with those psi!!!