hello, well my buddies 2000 Lincoln ls started idling rough so we took it to autozone and they scanned it to get a misfire in cylinder 7, so i pulled the sparkplug out, it was covered in oil i know i have to do the valve cover gasket, so i took the #7 coil and switched it with #5 and a new sparkplug was put in #7, now its still idling rough so we took it to autozone again, now we get the p0171 and p1131 problem codes... I've done some research and i'm guessing is the MAF sensor, could i clean it and expect everything to get to normal?