I have a1996 cavalier with 190k on it. Every once in a while (this has happend about 5 times), the needles on the dash will start jumping up and down, and power steering is lost. The car continues to run, however, if it is turned off, then it won't start unless it sits for about 5-10 minutes off. It will crank, but no spark. I have no idea what this problem may be.