I got a $1262.54 estimate from wheel Works to replace 4 02 sensors on my 2001 M-Benz S 430 according to their diagnostic that cost me $95. I got a lower estimate on the phone from Amana so I took my car in to have the sensors replaced and check engine light reseted. Luckly, it turned out that the O2 sensors were not the cause of the check engine light; it was cracked vaccum hoses. Vaccum hoses vs O2 Sensors = lots of savings.