TPMS misreading after flat tire repair?

[trajanl]

Hi,

I was hoping the board might have some insight into this . . .
I recently got a screw in my 2015 M3's front driver's side tire and had the tire repaired at America's Tire.
Immediately after leaving the shop, the TPMS indicated that the repaired tire was about 1 psi lower than the opposite tire. The next day, I had them refilled, and again, immediately after leaving the shop, the repaired tire was about 1 psi lower than the opposite side. Several days later, the repaired tire still reads about 1 psi lower than the opposite side.
Is there something about the TPMS system in which the reading would be off following repair of the tire?
Thanks for any insight on this.

Ed

[antych]

Did you reset it?

[trajanl]

Yes. Reset both times.

[Yessir]

Did you fill the tires after the car has been driven? In my experience when the tires are hot, it will throw off the sensor and cause a higher reading than normal. The hot air will then contract after cooling off possibly dropping the psi. It is best to fill the tires cold. This will give you an accurate psi reading. Or if you have real concern, test the psi manually rather than depending on the tpms. That will tell you if it is accurate or not.

[Yessir]

delete

[trajanl]

You're right -- I should compare the TPMS reading to the manual reading directly. Thanks for the reply.