2000 Hyundai Accent stalling on highway off ramps

I have a 2000 Hyundai Accent with about 108,000 miles on it. The car has been well maintained.

A few months ago, after a long drive on the highway at 60-65MPH, the car immediately stalled the moment I slowed down on the off ramp. The first time this occurred, it started right up.

On the way back home, the car again stalled on an offramp after a few hours of driving, and I refueled and added fuel treatment. It started back up after a few minutes.

On the final leg of that trip, the car again stalled on the off ramp, and this time it needed ten minutes to restart. It stalled (and was restarted) another ten times along the final mile to my home.

I took it to a mechanic the following morning, and he found nothing in the computer and nothing else mechanically wrong, and sent me home.

The car was fine for a few months, but yesterday it again stalled on an offramp after about 15 minutes of driving. This time, however, the car refused to restart, even after 30 minutes, and it had to be towed.

When the mechanics looked at the car the next morning, it started right up. There is nothing in the computer indicating a problem, and they say they left it idling without stalling for an hour. They can’t find anything wrong.

The previous mechanic suspected the MAF sensor, but said replacing it would be just a guess. This mechanic says it might be the distributor, but again that’s just a guess.

The car has never stalled during normal street driving. It stalls regardless of fuel quantity (full tank/half tank/quarter tank). There is no shuddering before it stalls - it just quietly goes to sleep and the Check Engine light comes on.

Any other bright ideas? Help!