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blue62 · 07-26-2021, 07:35 AM

Everything looks good to me with one possible exception.

In the third chart the post cat O2 sensor (green line) should be more like the yellow line.
More steady and above .450mv around .650-.750mv
"BUT" you did the test with a cold engine. The dips could also be from misfires or rise and fall of RPM.
So it could be fine.

When you get time you could test that post cat O2 sensor on bank 2 again as a follow up check or proof.
Do it after a good drive and at idle. you want a graph line more like the other post cat O2 sensor (yellow line)

You may also want to think about the alternator situation you brought up.
I had not thought about that.
Could very well be a factor in the misfire situation.

07-26-2021, 07:35 AM	#96
blue62 Registered User Join Date: Aug 2018 Location: Woodland Wa Posts: 1,309	Everything looks good to me with one possible exception. In the third chart the post cat O2 sensor (green line) should be more like the yellow line. More steady and above .450mv around .650-.750mv "BUT" you did the test with a cold engine. The dips could also be from misfires or rise and fall of RPM. So it could be fine. When you get time you could test that post cat O2 sensor on bank 2 again as a follow up check or proof. Do it after a good drive and at idle. you want a graph line more like the other post cat O2 sensor (yellow line) You may also want to think about the alternator situation you brought up. I had not thought about that. Could very well be a factor in the misfire situation.