Lichen 110 Posted June 6, 2018 A couple of days ago, I noticed that my right front tire was going flat. I filled it up and found that it was losing about 2 psi/hour. I could find nothing wrong with the tire. I filled it up again today and took it to Discount Tire. They said the tire was fine but was leaking air out of the TPS. They fixed it for free. Is this even possible? My first vehicle with TPS so I guess I don't understand how they work. Share this post Link to post Share on other sites
Bradywgn71 746 Posted June 7, 2018 Fancy valve stem with a pressure sensor and transmitter. There are rebuild kits for them as you found out. Share this post Link to post Share on other sites
Lichen 110 Posted June 7, 2018 Thanks, Chris. It's starting to make sense now. It was nice that they did it for free. Share this post Link to post Share on other sites
theksmith 4,019 Posted June 7, 2018 it could have been that they just needed to replace the valve core on it. there are 2 types of TPMS sensor designs, the older metal ones often also leak at the grommet/o-ring where it presses against the wheel. the newer design use a more standard looking rubber stem along with the sensor portion and IMO are a better design. they could still leak around the stem, but it's not as common. i kept shearing off the metal ones on rocks in my WJ, till i eventually gave up and yanked them all out. the JK came with the flexible stem design and it's definitely more rock-friendly. Share this post Link to post Share on other sites