Try to find a more detailed description of the codes, this will offer more clues.

RE EGR what type of failure ?

Fuel trim, long or short term ? Lean or rich limit?

MAF, high or low signal output ? shorted to ground or voltage? Open circuit?

I'd hang a volt meter or scope on the MAF output and watch it for an out of the ordinary voltage.

A hidden gem. On my 97 SL320 and 97 C280 With a M104 inline 6 and Bosch ME 2.0 / 2.1 compuer, if the computer detects a miss fire, it shuts fuel off to the miss firing cylinder. Your car might do the same. This slightly complicates diagnosis as an ignition fault will look like a fuel injector driver fault.