I took my BMW to get a full inspection of condition after my used purchased. The mechanic took me to the shop area and showed me the 02 sensor wire was rubbing on the drive shaft. He told me he would put a piece of tape on it and Zip tie it out of the way of the drive shaft. This was suppose to be done for free. Instead he put tape on it and left it to continue to rub on the drive shaft . This caused the wire to rub through and cause the 02 sensor to stop working and needed to be replaced..I believe this was an oversight on the mechanics part. The owner of this shop believes he's not responsible for anything..Don't take your car here. If you end up with a problem they will not take responsibility for it.