Last winter the little TPMS light came on on the dash. Checked the tires and they were all 10psi low (25psi instead of 35psi). No big deal and wrote it off as it being cold so I aired them up and never had another problem. Never saw the light all summer. Well first cold snap hit this year and sure enough the light comes on, check the tires and sure enough all 4 are back at 25psi instead of 35psi. Air them back up to 35psi (tires were around 40* when I did this and hadn't been driven in over 10hrs). Car sat for 2 more days and sure enough the light is back on and all 4 tires are back at 25psi. WTF is going on here. I know that the cold air makes the pressure lower but after two days of being at the same temp (~40*) they shouldn't all be losing 10psi. Even after driving 20 miles at 70mph they weren't up over 35psi. Is this a low profile tire problem or something else? I just find it really weird how all 4 tires are losing exactly 10psi after sitting for a couple of days. Maybe I'm losing my mind.

 

I would take to a shop and have them dunk them in water and check for leaks. Only should only go down 1lb of pressure for every 10 deg the outside temp changes so this seems excessive. Might be leaky tpms sensors, bad seal on the tire's bead, etc. Won't know until a shop looks at them. I'm guessing a simple fix.

 

Ya. Guess the heat from the summer sealed everything up but when the cold hits it opens up the gap and allows it to bleed off air. Maybe ill let infiniti deal with it. Tires never go below 25psi so I doubt its a nail in all 4 tires but wierder things have happened. Thanks.