Our 1995 850 turbo sedan with 180k miles has been exceptional so far. Lately, its engine may suddenly die; then I drive it off the road, and the engine starts right away with the first or second try until it dies again at a later time. In between these incidences, the car runs like new. The car started doing this about one year ago, initially once every 3-4 months. During the last two days, it has done once a day! There have never been any engine codes (last time they were checked was this morning) and there is no CEL. The maintenance of the car has been very good all along (bought it new with 19 miles, exactly 15 years ago). I am about to change the spark plugs (per volvo's schedule); the spark plug wires look good but have not been changed for quite a long while; and the car has a one year old battery (with some lingering issues). The fuel pump and fuel pump relay are the original ones. Any ideas about what may be happening, before I get stranded in the middle of nowhere? Thank you.

1995 850 turbo sedan, a really great car
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