What is the I/M area? Vehicle has a failed emmissions tests in an I/M area on 2006 Mercedes-Benz C280 4MATIC

Due to a check engine light being on, my vehicle with the above description did not pass yearly inspection the OBD inspection failed,and the MIL commanded on failed. There were two trouble codes reported, and they were as follows,(p2188 system too rich at idle bank 1 and (p2190 system to rich at idle bank 2).Advance auto did the onboard onboard diagnostic check. I would like to know is this a major or minor problem and what might be the estimated repair cost regarding this problem? E-Mail Address (

There's no way for me to estimate the cost of repair because I would have to diagnose the car to know what's causing the codes. Find a MBZ specialist.
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