1994 740i shows code of Cb on scaner idle is erratic when starting cold also makes code show up for both O2s whick are new.?

The "Cb" code on your 1994 740i indicates a potential issue with the engine management system, possibly related to the fuel mixture or air intake. Erratic idle when starting cold may suggest a vacuum leak, faulty idle air control valve, or issues with the engine coolant temperature sensor, which can affect fuel delivery. The O2 sensor codes could be linked to these issues, as improper air-fuel mixture can lead to incorrect readings. It's advisable to check for vacuum leaks and ensure all sensors and components related to air intake and fuel delivery are functioning properly.