N63 Oxygen sensor readings: what is normal versus what is wrong?

[JohnelP]

I did an Ista+ oxygen sensor reading on my N63 engine. One thing I am trying to explain is why there is a difference in the rate the downstream sensors recover from "full lean" (0.1V) to "full rich" (0.7V). I see the transition from 0.1V to 0.7V happens quickly after a quick/short hit throttle/release pedal on bank 2, while, same time, it is way slower for that transition from 0.1 to 0.7V to happen on the bank2. Pattern is roughly the same after a longer steady acceleration and then release throttle. Not sure that is normal or not.


No codes. This is the link:
https://youtu.be/ZEce-T1dWlA


I am thinking this slowness may be "due to oxygen reservoir" property of the cat, - though i need to read more ony how the cat converter is an oxygen reservoir? - to explain the slower transitions on bank1. they say the more steady, the better, due to reservoir capability. But I cannot certify that slower variation on bank1 is due to oxygen reservoir charge in the cat or something. Aka. -it is good or bad... Or the bank2 cat is almost out, as it lost its reservoir property and o2 voltage utput varies much more in synch with the wideband primary sensor, meaning the cat is almost gone.


Also I was hoping the steady state to be at 0.45V, not at 0.7V, that indicates a rich condition. At least at idle or 2k rpm, steady state, stays on ~0.65V. I was hoping to see it slabilize on 0.45V but it does not.

[328 Power 04]

If you have no codes, then it's most likely running as expected. Is there an actual problem with running?

If this is just stuff you were looking at incidentally, I wouldn't give too much thought to it. The logging features help a lot more when there's an actual problem. These engines have so many control routines and operating modes that random readings will not mean much.

[2001740il73]

Abel
Do you still fix software for air bag modules?

[JohnelP]

If you have no codes, then it's most likely running as expected. Is there an actual problem with running?

If this is just stuff you were looking at incidentally, I wouldn't give too much thought to it. The logging features help a lot more when there's an actual problem. These engines have so many control routines and operating modes that random readings will not mean much.

Actually, I was troubleshooting P0420 and P0430 on a ford explorer and needed the downstream /post cat readings, as I was not convinced a steady 0.8V at idle is right. But i see BMW is not far off either.
For the ford, I did today the ODBII Mode$06 test with forscan, and it complained of oxygen storage capacity. Attached a picture.mode6_ford_snapshotNov2022.jpg

Now, I was trying to replicate the ODBII Mode$06 test with ISTA+ for the BMW, but i could not find how to do it.
So, 2 questions:
1) How do i run ODBII Mode$06 test for BMW with ISTA+
2) What are my options beside changing cat converters for oxygen storage capacity complaints?

[BimmerBreaker]

Actually, I was troubleshooting P0420 and P0430 on a ford explorer and needed the downstream /post cat readings, as I was not convinced a steady 0.8V at idle is right. But i see BMW is not far off either.
For the ford, I did today the ODBII Mode$06 test with forscan, and it complained of oxygen storage capacity. Attached a picture.mode6_ford_snapshotNov2022.jpg

Now, I was trying to replicate the ODBII Mode$06 test with ISTA+ for the BMW, but i could not find how to do it.
So, 2 questions:
1) How do i run ODBII Mode$06 test for BMW with ISTA+
2) What are my options beside changing cat converters for oxygen storage capacity complaints?

what