Can't seem to understand this car

This car is giving me a hard time.( 2004 dodge intrepid ) I can?t seem to understand it. I have found a hose that needed to be fixed that help the rough ride a little. I still have a smell from the exhaust and lot of condensation coming from the exhaust. It keeps pop the same codes PO172, PO174, and PO175. (Which means lean and rich gas.) The check engine light comes on. Could it bee the gas that I use. (Cheep) or could it be another sensor. Also I could not find a EGR value, and not MAF sensor. Could it be the TPS sensor. Some one told me about a full sensor (were could that be and what is it) Help before this car kills me