My '93 died the same way, with low miles and about 8yrs old. I had to replace the OPTI. It was corroded on the inside. There was a modification somewhere around where you use the '93 dist. and the cap from a '96(which is vented). You have to buy a GM part(vent tube set up that attaches to the OPTI and tee off to the block vac. line). You can't use '96 dist, because the cam gear is different, but you can use the '96 cap. I did this and so far OK. I didn't replace the water pump(low miles) but I did have to replace the gasket. One of the toughest things is finding a 'reverse' torx socket (4mm?) to open up the dist to change caps. The dist & cap parts set up is about $400.
