1985 380SE stalls at idle

[spqrzilla]

I have just recently purchased a 1985 380 SE with approx 105k on the odometer. During the last three or four weeks that I've owned it, it has stalled on me during periods of idle. It seems to happen regardless of whether warm or cold. In fact, the first time it happened to me, the car had been running for at least an hour.

Most of the time, the vehicle will just stop while at a stopsign or a light while idling with my foot on the brake. It seems to be idling at just under 500 rpm by the tach. On one occasion, it stalled while decelerating.

It does not do it each time, and in fact has probably only done so about a dozen times so far.

Where should I look first on this ?