While driving, my roadster with 31,000 miles, the engine stops while going 45 mph and I was able to coast into a business driveway. I tried to restart many times without any thing happening. Called AAA and then decided tossed if top would clos. Top closed and then I tried to start car again. It started and I drove home. It has started since. I checked for codes and found none. Any suggestions before I try mechanic? Thanks for suggestions.