92 SC won't start

I have a 92 Super Coupe that won't start any more. I have $500 into already and no one can find out why. It does 1 of 2 things. It just continually cranks over and doesn't fire up or it turns over really hard and then kills the battery. I have replaced the DIS (ignition system module) and it seem to fix the problem for a week. ut now it is doing it againIt getting gas and spark.The problem started gradually and got progressively worse, to now when it won't start at all. Everyone once n a while it will start and seems to run find. The shop were I go has given up on it. Suggestions are welcome, getting ready to roll it out to the curb

yeah...roll it out to the curb.

Where in New York do you live, exactly?

Have the checked the exciter and pickup coil on the crank?

Sorry about the joke above, Rich. I was just telling my buddy how I wish I had an SC when I saw your post. Wish I could help, but if your mechanics didn't know, I sure as hell wouldn't. Good luck, and don't ditch that car!