Car shuts off like its not getting fuel.

What is and where is the opti-spark?

The opti-spark module is located on front of motor behind the water pump...it's what your plug wires plug into....I was having the same problem with my buick roadmaster, when I replaced my car has had no more problem and runs like a beast. If you go on youtube and type in: 1995 buick roadmaster opti-spark module replacement., videos will show you how to replace the module, I spent a few extra dollars and bought the high performance opti-spark module...