For a while now my truck has been misfiring at low RPMs on when moving in gear. I unplugged the map sensor and it ran great, but the thing I don't get is I replaced the map sensor and it did nothing, so I then replaced the EGR valve, that didn't do the trick, so I then replaced the o2 sensor that didn't do the trick, I thought it could be an exhaust leak and that still didn't do the trick, I'm thinking TPS, Spark plugs, Fuel Filter? anyone have any comments or suggestions, anything is helpful at this point.