[blix1988]

Hi, I have my E91 325i N52b25 for a year, and for all that time Emission Readiness shows incomplete for Oxygen sensors and Catalyst converters.

I tried the Drive cycle a lot of times, but nothing changes. There were never any codes regarding Oxygen sensors or Catalyst converters.

But the previous owner (bmw shop) could code so maybe theres something done to the DME to not throw errors? Should I update the DME?

Well anyway here is what I wanted to ask you guys.

I was monitoring rear / after cat oxygen sensors output and they are switching up and down, a lot, as you can see in pictures (red and green are rear O2 sensors bank 1 and 2). One bank is much worse than the other. Only time they keep stable around 0,7V is after a drive at idle. INPA shows the same.

Are my catalysts shot?

Car burns some oil, has unconfirmed 200 000 miles / 320 000 kms, history is nonexistent.