My check engine light is on. Codes report that my o2 sensor for bank 1 sensor 1 is bad. I replaced the sensor just to have the check engine light come back on. The only other thing I have notice is that there is some sort of missing wire on the top end. Could this be the problem? Help is much appreciated. Thanks. 1998 Zr2 4.3l

 

DTC's never tell you to replace a part, they tell you what circuit malfunctioned. It's the resposibility of the tech to follow the correct flow chart and determine what caused the malfunction. What DTC's did you retrieve? If there was more than one, what order were they retrieved in?