Repairs associated with oxygen sensor replacement

Hello, it's not so much about repairs associated with replacing the oxygen sensor(s), but it's about a rush to judgement that the sensor(s) are the cause of a problem, when in fact it could be something else. Diagnostic trouble codes will lead you do look in certain areas. "Lean" fuel codes, for example, will cause the engine's processor to ask for more fuel in relation to air, and this creates an emissions control concern and will cause fuel consumption and running issues. However, instead of a faulty sensor, for example, you could have a large air intake leak allowing unmetered air into the intake manifold. That's just a simple example. In the end, testing needs to be performed and data monitored to determine what is going on.