About 12,000 miles ago I told the forum that I would be the guinea pig for the group to test ownership without warranty. Today I am posting with the 2nd noteworthy event in this experiment.

My car started throwing codes related to the oxygen sensors. I actually posted this problem here last week I believe. At that time it was "internal resistance too high." With my Bentley I learned that this error is related to the heating element in the sensor but not the actual performance of the sensor. After carefully checking the wiring and cleaning the connectors I started getting "faulty circuit" and eventually one cylinder bank went to "B1S1 no activity."

Anyway, something up and killed both of my pre-cat oxygen sensors. It is too coincidental that they both failed at once so it must have been caused by a contaminant or something. Possible bad fuel? Who knows, but the sensors were gone and I have no warranty.

So I checked with my favorite parts source vwparts.com and a new OEM sensor is about $180 and I needed two. OUCH!

Being the crafty guinea pig that I am I crept over to the S4 forum to learn that there is a VW part number that is the identical Bosch 4-wire heated sensor with a different plastic plug for the wiring. Get this, the VW part costs $22.96. For future reference the part number is 06A906262Q and it can be purchased at this link.



To install the VW sensors you have to first remove the old ones from the car and then splice the old plugs onto the new sensors. Basically match up the 4 wires by color and splice it together. I did a really thorough job with solder and heat shrink tubing as well as covering the whole splice with the plastic cover that was on the wiring to begin with. Nobody looking in there could ever tell that they are spliced in without taking things apart. I do not consider this to be a "hack" repair to save a few $.

Removing or installing the pre-cat sensors in the allroad requires a oxygen sensor socket (with split is side to accomodate wiring) and a really long extension. You attack them from above and diagonally from either side behind the engine.

Anyway, the real point of the update is this. I am at 62,000 miles and have had to pay the following out of pocket:

$180.22 - Fan Control Module
$53.95 - 2 Oxygen Sensors

$234.17 - Total cost out of warranty as of this post

Of course I also have significant labor invested as well, but I can't quantify that as easily. I actually much prefer doing it myself anyway so I see it more as a benefit than a cost. This is the only way to know that it was done right.

One final thought - if I were covered by an extended warranty would it have even covered this? Are O2 sensors considered consumables?

+ + = 451whp/472 ft-lb

Full RS6 bastardized allroad quattro alive and on the road.