my mass air sensor was going out but not dead and did similar things to me. if your car is a 3.8, they will run with the mass air sensor unplugged since there is a speed density sensor too. if the mass air sensor is bad, and you unplug the mass air sensor and the car runs better off just the speed density sensor you'll know its mass air sensor or wiring. that's what happened to me back in 2010 hence my 2010 join date.