I just did a stomp test on my 93 525it after I had a CEL go on yesterday. I know that the code is for the O2 sensor, but is that what I should immediately replace or could it be a host of other problems. I am new to this and would like any experience that you guys could share. It had the surging problem before the CEL went on and then immediately after the CEL went on the surging went away. Please help. I am ready to replace the O2 sensor, but didn't want to jump the gun. Thanks,

Jeff