[El Gringo]

I Have a 09 E91 I have replaced the valve cover, mostly all the gaskets that usually have oil leaks also the vanos Coils, Spark plugs and I reset everything and erase all the codes I’ll drive it for three or four days and then the Service Engine light comes right back on. These are the codes that I’m getting. 2A13,2F71,A2CD if anyone has had this problem, please let me know how to fix it. Thank you in advance.
Also, I forgot to mention when I first turned, the car on the idle goes up and down for a little and then it just idles normal.

[gbalthrop]

You appear to have FOUR unrelated issues:

1) The "up/down" idle RPM on startup may be due to "UN-metered" (by MAF Sensor) air leaking into the intake manifold, perhaps due to a cracked or leaking hose between VC & Intake (caused when VC removed?). If Idle RPM is steady when MAF Sensor connector is disconnected (you WILL get fault code for disconnected MAF), that confirms a "Vacuum Leak".

2) 2A13 Code is for issue with Activation of DMTL Pump. That pump only runs after engine shutdown, to test for air leaks in tank sealing system (Evaporative Emissions). No effect on engine performance. If you have emissions inspection, that will cause fail. Here is BMW Fault Code Lookup "Fault Info" link:
https://bmwfault.codes/DiagView?id=M...E4NTA2ODYwNQ==

3) 2F71 Code is for issue with E-box Fan NOT activating when temperature in E-box (where DME is located) exceeds ~ 40C. Here is Fault Info Link:
https://bmwfault.codes/DiagView?id=M...E4NzU3MzIwNQ==

4) Your Controller is reporting undervoltage. There is NO Fault Info sheet for that code, & I know nothing about that one:
https://bmwfault.codes/Lookup

I would BEGIN with the E-Box Fan code, as summer temps are NOT healthy for dme, without that E-box fan. We can provide ISTA wiring diagrams & suggestions IF you provide:
1) Last-7 Characters of your VIN;
2) Make/Model of any Scan Tool or diagnostic software (INPA/ISTA) available.
3) Whether you have a Multmeter ($10 entry-level tool for electrical diagnosis, Amazon or HFT).
George