ROUGH IDLE & CODES:

[Bmwtvboy]

I have a 2001/x5 3.0 auto. It has 173K miles. The O2 are all original. Last month changed out the CCV with a new insulated kit ,used the old throttle body gasket. Ran fine but started to run a little rough and the SES light came on. Coded it and this is what came UP. They all prefix with a P.
1085 Fuel Control Mix Lean (bank2 Sensor 1)
1348 Misfire /start cylinder 4
1347 misfire cylinder 3 with fuel cut-off
0300 Random Multi Cylinder Misfire detected
0171 System to lean Bank 1
1343 Misfire cylinder 1 with fuel cutoff
1741 Couldn't find this one on the code page.
1083 Mixture lean ( Bank 1 Sensor 1)
My mechanic friend then stated "vacuum leak" so we put a new throttle body gasket in, checked hoses and connections and all was great. SES was turned off. Drove away and it was like new again, an hour so later, SES on but still driving smoothly. Two days later, filled it with full tank of same gas. Low octane because I have been getting about 14 mpgs notice this a couple of weeks ago after the CCV change out. Then today, it started idling really rough, engine vibration, and misfire , loss of power. Shut it off, set 20 minutes , turned it on and it seemed to idle/accelerate to 3000 RPM's smoothly in park.
What to do? I imagine I need a full set of O2's. Perhaps a tune up? Last one was at about at 90K and the I.coils are original. There are no other lights on the dash. I did have to pull the rear fuse to turn the radio off as several weeks ago it wouldn't turn off. Top light bar with time clock stayed on dim.
But nothing else stands out. However, it needs a new left drive shaft boot and the passenger door broke. These seem common. Don't know if I just need a new door carrier or the handle as well. It's a bimmer after all.