Since your car has the M112 V6 engine, you can be sure that the mass air flow sensor is behind the fuel trim codes (p0 170/173).

The EGR code is most likely a partially plugged tube that allows exhaust gases to flow into the intake to reduce N0x.

Air injection code can have many causes. BEST diagnosis is done with a dedicated scanner that can trigger that system to operate & then show the results.

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