codes 1a,1b,1c,1d

Hi everyone, it is being a while without any problem in my car bmw 01 540i, now it started to failing in the low revolutions, it looks like it is going to stop, but it doesn't, it goes up again. when it is in a still position, in neutral the revs stay at 500 then start going down and up without any reason.
I had a code reader from bavariuan auot sport, I connected to see what kind of codes will bring.
So first gave the OF code, then showed the following codes:
1d, 1c, 1a, 1b and 8c and finally 5d.
I look into the manual and show me that
1a - Mixture control, off iddle, cyl 1 to 4
1b - Mixture control, off iddle, cyl 5 to 8
1c - Mixture control, iddle, cyl 1 to 4
1d - Mixture control, iddle, cyl 5 to 8
5d - Evaporative emission system.
8c- Map control thermostatcircuit/control
Now What I need to do? What do I need to fix?
I need your help to solve my problem before it goes worst or it let me stuck in the road.

thanks.