My car will start most of the time, sometimes it wont start no matter how many times I try and if I leave it alone for 10 minutes it will start right up. The car also runs fine up until you hit 3k on the RPMs and the engine drops all the way down and will not accelerate past that.

It is a 92 RS 305

 

Look at the injectors. Some ytimes the wires will get pinched under the air cleaner. Have you ever serviced it? Plugs, wires, filters,etc? Any service engine light?