Every once in a while my 94 D90 misfires and this leads to the engine sounding like it is starved for gas as it quickly shuts down and shuts off. So I'm forced to pull off on the side of the road and "sit". But only for a few minutes. Because after, say, five minutes, I can typically restart it and the problem disappears. The problem may not return for days or weeks or even months. But when it does return, I'm forced to do the same thing: sit and wait and restart. Any insights as to why this is happening?