I have had a persistent problem with tire pressure in passenger side front tire. If any of you can help me with this problem I would greatly appreciate it. Right front tire has been losing 2 pounds a week for about a year. I have had the car into my MB dealer three times over this problem. Twice they reglued the tire and the last time they said they had to replace the gateway for the TPMS. While they were at it I told them to replace the tire valve. The tire is still losing 2 pounds a week. What could account for such a consistent loss of pressure for such a long time? I have the original Conti tires on the car and they appear to be in good shape. Plus you would think that a defect in the tire would get progressively worse over a one year period. I am wondering if it could be the rim or if the TPMS is somehow causing the loss of pressure. HELP.

 

I had a tiny crack in my wheel that made the tire go flat very slowly but I would think your Dealer would have found it if you have one. Could be just a bad tire.

 

May be your tire is on a diet

Easiest way is to try w/ a new tire..... if it's still losing air, it could very well be the wheel... it may be bent.

 

Could be anything from a simple leak at the bead to a cracked rim.

Take it off and spray a soap water solution all over the tire and wheel. Pump the tire up to about 40psi while you do this. You should be able to find the slowest leaks this way.

 

Smart!!! Didn't think about that.

 

dsc,

On your cracked rim, do you know if you hit a pothole?

We've had two cracked rears now (one left, one right) on our W211 E55. Left was bent a bit supposedly and cracked, right has now cracked. Both times we found the tires flat, took it in to find the cracked wheels. I'm not sure what's going on with the quality of OEM MBZ wheels but cracking wheels on <minor> potholes (if that, we've never hit a major pothole) is just silly. We've had zero issues with Audi, Porsche, VW OEM wheels, even 19" aftermarket rims with 35series tires, only MBZ OEM wheels.