X3 on the blink with these codes...HELP!

[GT456!]

Trying to get me 1st gen X 3 back on the road. M54 3.0. 234k on the clock
Codes I'm now confronted with...
2783
2786
2787
She cranks now and is constantly surging at idle.
Installed idle control valve resulting in...no improvement.
Any first hand experience is welcomed.
HELP ...

[X5Sport]

2783 is for the Mass Airflow sensor (MAF). The other two are also connected with airflow as well.

2786 is for the Additional Mixture Adaption at idle speed - which would explain the surging. Worth looking for a split or leaking hose in the air inlet side. Error often triggered by air leaks.

2787 links to a possible issue with the throttle valve or mixture setting so could be being driven from the 2786 issue.

All three seem to be linked with air flow and/or air leaks in the inlet side.

[GT456!]

Thanks for your help...I did remove the air intake to replace the starter...all went back easily.
Did you view the pic of the boot and the burn spot at the throttle body connection?
Any idea of what that's all about. I never smelled anything burning.
Thanks for your quick reply.