97urS6

Going to be switching over to a set of winter tires this week, and will be using a set of 17" flat-five rims from my last car, an '03 A6 4.2. I was able to pick up a used set of tire pressure sensors and new valve stems (that are supposed to work with the sensors. But I have never really installed these before, not sure that the tire shop that is going to mount the tires have ever seen these before either?

They look like the stem just bolts through the sensor on the inside of the rim? But how tight do you crank the bolt to? Should they use lock-tite?

Is there anything else they need to know or do? Is there anything that needs to be done in the MMI to make the car recognize the new sensors? I have seen a section on resetting the sensors somewhere in the Car/System/Tire Pressure menu?

Any help will be valuable.

TSHong

They need to be torqued to 35 inch/lbs or 4 Nm. There is a hole in the back of the sensor so you have to put a drill bit or something like so the sensor doesn't spin while you are torquing the outer nut.

Not sure what Tire Lock is so I can't answer that question.

Also you are correct, after you replace the sensors, you have to reset it under the tire pressure/ Reset or Relearn sensors. I can't remember the exact wording. Also it takes a while for it to relearn so be alarmed when it doesn't happen in a few minutes.

MP4.2+6.0

Actually in OE, there are two fasteners. On the inside is a small Torx screw. It is pre-treated with Lock-Tite. Basically you hand tighten it with a screwdriver type Torx wrench, and with the LockTite it isn't going anywhere. You only tighten it with the sensor placed inside of the wheel so that the body of the sensor hugs the barrel closely once the valve stem is in place and the angle of it set simply by pushing the sensor body against barrel. Meantime you tighten the outer nut to wheel face. That is what holds sensor assembly in place. It is metal colored plastic BTW, so again you go gentle. Given the sealing washers and such in between, I don't see how it would come loose in general either. I have never used any thread compound on these.

Once you see it in place, it is pretty basic. The D3's use the same Beru/now Huf sensors used on a whole generation of Euro cars from Minis to BMW's to Audis to most all--until they shifted back to the ABS type the Asian and American manufacturers mostly used--only starting in later years when the system became required after the Ford Explorer/Firestone debacle. Thus, most any decent tire or brake type shop would know them if they deal with most any Euro brand from the mid 2000's. Unusually, the D3 had the full display, but most all the Euro ones had similar in wheel sensors.

97urS6

I corrected that typo... "lock-tite"

TSHong

Roger that. Also forgot to mention the plastic nut/cap on the outside is a one time use part. You need to purchase repair kits, which come with a new core and cap, and are very inexpensive.

97urS6

Yep, I picked up a full set of new valve stems from Huf. So I think I should be good to go. Thx so much for everyone's input.