Rough idle and sputtering

Okay, the car first off starts first crank every time even on coldest winter day. It idles rough while in drive or reverse but straightens out if you put it in park or neutral. It seems to stumble when applying the gas on the road and cut out occasionally around fifty five mph. When it cuts out I lift off the gas pedal and reapply to keep moving. It does not shut off when idle is rough at stop signs and such but it sure acts like it wants to. It seems there are a hundred different parts that could cause this so I am asking for help tracking the real issue down. So far I have pulled the MAF sensor and cleaned it. It seemed to help once or twice but I have since cleaned it again and no change was the result. Could it be a plug and wire problem even though it fires up first crank? If not any other suggestions. Thanks in advance for any help I have tried to have it scanned at a couple auto parts stores but they claim it is too old or their scanner.