OBDII Warning Won't Clear

[elripster]

PS - Prior to the engine and cats fully heating up the it seemed that the O2S1 and O2S2 signals were both oscillating between around 0.1V and 0.9V... as it got hotter the O2S2 sensor swings got smaller....

Also, interestingly there appear to be no contacts in the Ox1 and Ox2 pins of the diagnostics connector on my '97 80... So my hopes of being able to observe the O2 sensor signals easily and without the OBDII app have been dashed... oh well...

There are cheap apps that work well. I use Torque. You can see O2 voltages realtime, even log data.

 

[flyingmonkey]

So for those of you that have been following along I was able to pass smog. If you are wondering what I did to fix this, the answer is NOTHING. I did nothing. Catalyst monitor is still not clearing and there is still no trim reading being recorded by 2nd O2 sensor. I took it to a different smog shop and it passed. After it passed I asked why would it have failed in the first place. He said he didn't know because 1999 and older vehicles should pass with one or two monitors not being cleared. He asked if the CEL was cleared or if the battery had been disconnected prior to the inspection I failed. If that was the case, more monitors could have been popping if I hadn't driven around enough. That's probably what happened since I clear 0420 CELs pretty often. Either way, she's legal again. Thanks to everyone who tried to help get this resolved.

 

[elripster]

Awesome! I did buy the scan tool and Torque app so if you ever need to scan/plot data let me know.

Frank