If the Mass Air Flow meter is going bad, it will usually cause the car to sputter, misfire, and run rough. What the MAF does is meter how much air goes into the motor, and it adjusts fuel to match it, to get the best air/fuel mixture for the RPM range. If you disconnect the MAF while the car is at idle, the computer will go to a set air/fuel mixture that should make the car idle smoothly.
One way to find out if the MAF is bad, is to turn the car on, and if the car is running rough, disconnect it. If the car runs smoother, then the MAF is probably bad, if it runs the same, then the MAF is probably good.