Just as a rubber valve is now cut out and replaced by a new valve when mounting a (new) tire, the TPMS valve must also be serviced to ensure a good seal, both for air leakage and the influence of moisture and dirt.

1. Replace the sleeve nut and the rubber sealing washer
2. Replace the inner valve with a new one (nickel plated)
3. Tighten the sleeve nut and the inner valve with the prescribed tightening torque, so NOT on the feel !! Over-tightening, or repeated tightening and loosening of the inner valve can cause surface damage to the nickel coating, which will immediately initiate galvanic corrosion. Use, or buy, a valve wrench with torque and discard the old one to avoid problems!
4. Inflate the tire to the specified pressure and check / correct the tire pressure when the vehicle is on the ground with normal load.
5. Install a new and correct valve cap with an internal rubber grommet to keep out dirt and moisture.