My typical procedure when a car comes in with the low tire pressure light on is to first check all the pressures, because temperature changes can cause all the pressures to change equally and cause the light to come on, and then if only one tire is low, I then put it up on the lift.
Once it’s in the air, I spray down the whole tire, beads, and valve stem with soapy water. Wherever it’s leaking will cause lots of little bubbles. On this particular car, I sprayed down the right rear tire, waited a couple minutes, and when I came back to it I immediately saw the leak.
I told the service advisor and he told me to plug it, but then when I took the wheel off I noticed a second leak.
So I looked closer, and found another.
And another. Surprisingly the pressure in the tire when it came in wasn’t very low, so even with so many leaks they must have been very slow leaks. With four punctures I was done looking because by the second one it needed a whole new tire. Luckily the rest of the tires still had decent tread life left, so we only had to replace one tire. It’s always a good idea to check for more leaks when you find one.
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