a majority of the time when I come to a stop my engine stalls out, my check engine is on with 2 codes of P0170 Fuel Trim Malfunction (Bank 1) P0171 System too Lean (Bank 1), I'm not really too sure how to fix these two problems, but I think the most common problems are my O2 sensors, a possible misfire, and fuel filter, even so I don't know how that would stall out my engine when I come to a stop, (it usually acts up when speed is decreasing around 30 and below) any advice would be greatly appreciated.