True MYSTERY problem. p2096 Can you help me?

[Persian]

Background:

For the past winter, I was going to and coming from school with a jammed open Thermostat. (freezing my ass off)

I didn't have the time to look after this due to an intensive program I was in. About 80 hours per week at school.

Fast forward to March where my sticker expires and I need an emission...


I had the codes:
P0125 (thermostat open code for BMW).
P0313 Misfire with low fuel
P2096 Post Cat Fuel Trim System Too Lean Bank 1.

OR in BMW language Trimming, oxygen sensor behind catalytic converter, bank 1.

I purchased the thermostat and a MAF (preventative) straight away. I replaced both of these. MAF is VDO Siemens.

All codes cleared and p2096 kept coming back.

So I purchased and put in a new o2 sensor after reading my voltages and seeing that the sensor was "stuck" at a voltage.

While I was at it I checked all the hoses and noticed there was a hose with a slight crack and I fixed it(it isn't part of the vacuum, but it does come into play when the car is NOT idling, it is connected to some solenoid or stepper motor).

The new sensor surely worked.

But now the code continues to come back, AND O2 readings spike at 0.1 to 0.6~0.8 while driving.

What can the problem be? Is it the DME? Is there a non-computer reset which may work?

This is a video from someone else whom appears to have the same issue!

https://www.youtube.com/watch?v=Ndif0o24VsU

I left him a message, hoping to hear back...

Car runs like a DREAM. 265,000 kM

PLEASE HELP ME