Questions and Answers

Acura Legend Oxygen Sensors Q. I have an 1988 Acura Legend. I have recently had the Check Engine Light come on. But once you turn the car off, the light turns off. I believe the 02 sensor has gone bad, but my question is how do I tell which one it is? There are two of them and they are only single wire sensors. Do I need to wait until the Check Engine Light stays on all the time to tell which one has gone bad? Thank you for you time, Aaron

A. Even though the Check Engine Light is off, there will still be a DTC stored in the PCM. You can pull the DTCs from the computer and see what the code is. If it is the front O2 sensor, a code 1 will be stored. If the rear O2 sensor is bad, you will get a code 2.

You can find information on accessing the DTCs and what they mean here; Diagnostic Trouble Codes