Ah yes, isn't that a great feeling when all of the sudden the the throttle pedal ceases to do anything? Sure adds an element of excitementand anticipation to any drive. Has happened to me many times (too many). My first reaction is to depress the clutch pedal and try to rev the engine. Wait too long and the engine will stop. As you experienced the result is a lack of power steering and brakes. This is nice when you're on the highway in the left lane because the car doesn't slow down as fast - allowing some more time to coast to the side of the road. Leave the car in gear and you'll slow down faster, but since the engine is still turning you'll still have power brakes and steering.

I've always attributed the problem to fuel. At least with my OBD I car ('95 854 NA 5-speed). The computer should have tripped a code for an ignition or sensor signal problem. Did the car eventually restart? Mine would restart after sitting for 5-10 minutes.

The last time my car had this problem I replaced the fuel filter after which the problem disappeared (it had been happening more and more frequently up to every time I drove the car). After seeing the greyness that came out of the filter after 150K miles, I'd recommend a fuel filter change out for any 850/S/V70 with more than 100K miles. Other suspects are the pump relay, the pump, or the fuel pressure regulator.

-Will
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850 / 240 / Mini