Car stumbles, like a hard shift, and then goes on. If idling, rpm goes down, up, and back to normal. Could stall. It has new plugs & wires & fuel filter. If I plot the output of the maf with a scan tool, it goes along nicely at 0.2 to 1.8 lbs/min. Then occasionally, it will spike for a fraction of a second, usually up to 41 lbs/min. That is when the car jerks and stumbles. Then back to normal for a while. It may be a few minutes until it spikes again. If I take out the maf, it reads a constant zero. If I blow toward it, it picks up a small breeze. If I leave maf in but disconnect it, the car runs fine. Once in a while, it sets code P0102, but that is LOW voltage out and I seem to have a high voltage at the spike. The maf is very expensive, more than a whole computer. Can I be sure it is the maf? Could it be something else?