[d1saster]

Just wanted to share my experience.

Usually I rely on the TPMS to tell me if the tires pressure is low. Without any warning I've been driving without worrying. I was heading on a road trip and checked it before I leave and the rear passenger tire was 22 psi, the other passenger 28, fronts were 30. The recommended pressures are 35 front, 38 rear. No low pressure warning ever triggered. Inflated the tires to recommended and after 400 miles I checked again to see rear passenger was about 28 psi?!! Inflated again to see later it dropped. I reset the TPMS to recommended pressures and after that I got low pressure warning every day. It appears I've constantly been driving on low. Decided to tighten the valves with torque wrench set to 35 inch-pound but it keeps rotating since to torque it properly I have to remove the tire from the wheel. After two days no loss of pressure. It appears tightening the valves worked.

My advise is for people with TPMS to check their pressures since BMW do not reset the system from the factory. Meanwhile I will code off the acoustic warning and leave just the icon if appears.