Hyundai Repair: Check engine light, technical service bulletins, numerical digits

Question
code said that the O2 sensor was bad. put a new sensor in, light came back on after two days. when i got the car there was no sensor in that spot someone put a plug in the spot for the sensor. after three sensors the light in still on.

Answer
Hi, Rick.  An oxygen sensor code simply means that the oxygen sensor readings aren't what the engine control module (ECM) expects them to be.  This can be due to a problem with the oxygen sensor or any number of other components.  Often, a leaking exhaust can cause an oxygen sensor code to set.  In some cases, there are ECM updates to address erroneous oxygen sensor codes.

To provide you with specific information about what is wrong with your vehicle, I'll need the following information:
1.  The specific trouble code (of the form Pxxxx) where the x's typically represent numerical digits.  This will tell me the specific issue the ECM had with the sensor readings.
2.  The year and model of your car as well as which engine it has.  This will enable me to know the specific system on the vehicle as well as to look up any pertinent technical service bulletins (TSBs).