OK. Check engine light came on and so I went to AutoZone. They pulled the following codes P0170 ,P0173 and P0161 all of which they told me were O2 sensors. Now I don't believe in all going faulty at once so could it be the MAF?
My car runs very well accelerates great etc. so is it the MAF or sensors?

I've searched the board for similar situations but wanted some expert advise, if this is just a MAF issue I'll do it myself. If it's more I'll take it to the dealer.

 

I'm not an expert (I have changed my MAF twice in the past year though) and sometimes your ECU makes up for a bad MAF until it totally fails. I didnt know my MAF was bad until I disconnected the battery and when I drove after reconnecting it, it was very sluggish. I dont know if this is making any sense but your MAF may be on its way out but not there yet.

 

P0170 ,P0173 directed me to my MAF sensor and I replaced it and it did wonders. If you're over 50K miles on your CLK, chances are, it's your MAF.

And it's a 10 minute job to do it yourself.