Can tire pressure go up and down without any air being put in them? My tire was down to 26, i put air into my tire and it was over inflated. I checked the automatic gauge and the other 3 were down also . A day later they went up a little then two days later the 3 regular inflated ones were normal and the under inflated one went back to an over inflated 37. ?
You don’t say where you are or what the current temperature is . Go to a tire store and have the tires set at the correct pressure , see what your dash read out says . Right now you are guessing and if you are in the desert a highway trip will cause the pressure to increase but not enough to worry about. You should also have a real tire gauge just to confirm what the dash readout says.