I have a 2005 Dodge Durango 3.7L. A few weeks ago it started misfiring and hesitating on acceleration plus gas mileage cut in half. Vehicle is getting codes P0175 and P0172. I have had the thermostat, water pump, tension pulley, MAP sensor, spark plugs, coils, and O2 sensors replaced but no luck with fixing the issue. One of the causes is listed as a MAF sensor as problem but my vehicle does not have this sensor (although there is a small sensor on the back of the breather that I am not sure what it does). Can anyone tell me what else might be causing this problem?