So the problem is back. I thought I had fixed the issue, I tightened down a few loose electrical connections and check for grounded wires, to no avail. The car did run fine for about 300 miles before showing off the problem again. My 87Si has been acting like the alternator is dying. At low RPMs the voltage light comes on. This problem also seems to be causing the engine speed to jump up and down, much like a vacuum leak would cause. It's not the alternator, it was tested and tested fine. I also tried a new alternator and the car did the same exact thing. The battery has been replaced since this issue began and I also changed the battery terminals just in case. None of these things provided a change. If you need to know anything else, just ask.