Emission Control problems of the 1999 Infiniti QX4

Consumer stated O2 sensor was causing check engine light to come on and stay on. This has been going on for the last 6 months. Consumer took the vehicle to the mechanic, and was subjected to having a wiring harness installed. Consumer had that done, but it did not solve the problem. They were talking about another $1200. 00 to repair something else.