I had the same problem on my 95. (although thankfully the 85 911 also had the same problem so I learned from that), it is the DME relay. I guess when the relay fails it stops the fuel pump from working and hence no start. In the fuse box under the hood, pulled out the old one, popped in the new one and it started right up. Its a very simple and pretty cheap (like $30). It should be more widely publicized. but it can just go out at the drop of a hat, with no warning. Its a good idea to keep a spare around so you dont have to wait when you order one. Sometimes its the simplest things that we overlook. I was thinking it was the fuel pump too until i remember the DME relay. Hope this helps!