Volkswagen Repair: Oxygen Sensors, oxygen sensors, oxygen sensor

Question
Two weeks ago my "check engine" light came on in my 2002 VW Beetle.  The code came up as the oxygen sensor, so I had my mechanic replace it.  (Not the dealer)  Three days later, the light reappeared.  It has been coming on and off ever since.  I am so frustrated!  This car has really been a big problem for me.

Answer
Well there are over 250 reasons for the light to come on. An O2 sensor fault has many ways of failing. The P0# for the code would be the best. The VIN# as well. The technician which looked at your car should recheck the faults and the quality of the work. Keep me in touch and let me know how it goes.