jargoude

Anyone heard of this issue before:
Front right tire was leaking, took to tire shop, and they stated that stem is cracked, need new TPM sensor, then 3 weeks later, the front left tire loses air and same issue? TPM stem cracked. I asked what would cause this and they said that freeze/thaw may cause it or simply "age". I am not sold on this theory yet. Searched the forums and couldn't find an answer. Any help would be greatly appreciated. Car is out of warranty so it will cost me $150/a piece to replace unless anyone knows of any other sources.

Distinct

I'm glad I don't have TPMS in Canada. I have it on my Wife's Infiniti and it's a pain in the *** getting the dealership to reset the sensor light each time I switch winter and summer wheels.

Cold weather changes really should not be causing the TPMS to fail structurally.

jadewombat

Try the Tire Rack, I think they're cheaper for the sensors. Don't remember quite what I paid but the extra set of tires for autocrossing were about $78 each and the sensors were a little less than this.

AZN Optics

Something you should know about OEM MB TPMS and is fairly well known among aftermarket wheel shops that deal with a good chunk of MBs.... The TPMS sensor has the rubber seal inside what can only be described as a cup shaped holder. As such, the amount of usable rubber that extends past the lip of the cup is actually very tiny and can very easily lead to improper seals. What most good shops will do is sand down the lip of the cup so you have more exposed rubber and can more tightly seal the TPMS in. Keep this in mind as most crap shops will just blame it on a cracked TPMS sensor instead of really getting down to the root of the issue.

jargoude

Thank to all for the info and especially AZN.....I will see if I can find a good shop to look at this and do for me.

Matt_Eurojerks

I think I am having the same problem with my driver side rear wheel. I want to pull my hair out. Every few weeks I get a warning.

RLE

Using a 7/16 socket, tighten the nut around the valve stem just a little. If you can turn it a little then tighten all four. Reset the pressures and the TP sensor system. Check that tire's pressure after a day or so to see if it's still leaking.

Over time the sealing o-ring (inside) will shrink a little.

This fixed my sudden leak last year and it has not returned.

Matt_Eurojerks

thanks.

UK-C200

FYI, torque for the nuts on the TPMS stems is 8ft/lbs - so don't tighten them too much. You can also order stems separately from the sensors.....

AkaSigFreak

The rings can also dry-rot over time. Tire shops should have the rebuild kit which is around $10. This solved my problem.