Got codes 0136 & 0138 which is for the O2 sensor in Bank 1 - Sensor 2. Anyone have a part number and maybe a pic or howto. I've got to change it today, card is changing hands either tomorrow or Monday.

Part # for right post cat is 13550, 13552 for left.Awkward to get to and on my car very tight. I tried for an hour to loosen it. Gave up and paid a local shop $40 to swap it and save my knuckles.<ul><li><a href="http://forums.audiworld.com/12v/msgs/6482.phtml">http://forums.audiworld.com/12v/msgs/6482.phtml</a</li></ul>

And is sensor 2 definately post cat?

Right side of car after cat. Has a bright green plug.<ul><li><a href="http://www.bentleypublishers.com/tech/audi/audi.dtc.table.htm">http://www.bentleypublishers.com/tech/audi/audi.dtc.table.htm</a</li></ul>

So I went the the shop to get one today. 1st: audi, they wanted somewhere around $180, and my hookup in the shop could get the price down do $135. I passed. Next shop, they wanted $110. Pass. Next shop, wanted $90, Pass. Then the mechanic pulled me aside and sold me two (sensor 1 and 2) for $20 a piece. I pretty happy w/ my expenses right now.