Technical Description
The oxygen sensor circuit is responding slowly on Bank 2, Sensor 2.
What does that mean?
This diagnostic trouble code (DTC) is a generic powertrain code that applies to OBD-II equipped vehicles. While it is a generic code, the specific repair steps may vary depending on the make and model of the vehicle.
This code pertains to the rear oxygen sensor on the passenger side. Bank 2 refers to the side of the engine that does not contain cylinder #1. Sensor 2 is the second sensor downstream from the engine.
This code indicates that the engine’s air-fuel ratio is not being adjusted as expected by the oxygen sensor signal or the ECM. It may not be adjusting as frequently as expected once the engine is warmed up or under normal engine use.
Symptoms
You will likely not notice any drivability problems, although there may be symptoms present.
Causes
A code P0159 may indicate that one or more of the following issues have occurred:
Possible Solutions
The simplest thing to do is to reset the code and see if it reappears.
If the code returns, the problem is most likely the rear passenger side oxygen sensor. It will likely need to be replaced, but you should also consider these potential solutions:
