why does my buick just crank and when I let off key it backfires?

I understand your point, and yes I went through those days as well, and never dreamed I would end up being a mechanic, you see it hate to get dirty, lucky me. The module is, I believe it's been awhile on those, on the back side of the engine, and the coils are attached to it, be careful when removing it because if it's the one I'm thinking it is, the crankshaft position sensor is attached to the underside and sticks into a hole through the block. Check the power wire going to it to ensure the battery voltage is there during start and run positions. If it's to be tested you need someplace that has an ignition module tester.

kk ty. one other thing just thought of. would my alternator have anything to do with this, when the car is running the gauge reads like 15-16 it is in the red on the gauge and the volts light is on. just asking cause u mentioned voltage.

That's pretty high, if you were close I would show you how to change the voltage regulator. It's in the alternator, and will ruin your battery and could have caused some of your damage if you have been driving it this way for some period of time. Let me know if you have some more questions, I don't mind until I go the bed, and will be around some tomorrow. I get Emails on my phone as well.