Oxygen Sensor code... but both output same
I did a search here regarding oxygen sensor issues, but am in need of technical advice on my E34. The car has two upstream sensors (540). I have a Snap-On Solus computer tester that denotes that the car keeps setting a code for the #2 O2 sensor.
The sensor is supplied with 450 mV from the computer and is suppose to output 450 mV, plus or minus 300 mV, depending on whether the exhaust is rich or lean.
Testing the output from each o2 sensor, I am getting approximately the same values from both, with #2 reading 50 mV more lean than #1, and it does not seem like the update rate is as fast as it should be.
I do not have any exhaust leaks before the sensors, and have tested the engine for vacuum leaks. I have a hard time believing that I have a bad O2 sensor, when they are reading about the same testing them individually with a Snap-On Vantage.
If anyone can help me out, I would appreciate it. Has anyone ever gotten an O2 code when there was something else wrong? Love the forum... thanks.