Originally Posted by oilcanhenry

Might be able to determine that with a vacuum gauge (seems like no one uses those anymore), unless that's the gauge the mechanic used. Yeah, the distributor bearing going out is something I've never seen before, but sure, it could do this. You learn something new every day in life. Might have a small intake manifold leak. I've seen people actually spray gasoline on the manifold to test for leaks, but something less flammable, like WD-40 would work as well, IME.

I've heard of people using different substances to clean a catalytic converter out, like Methanol or Acetone (don't use without gloves and a filtered face mask as these can go right into your body though the skin), but I've never seen it done for myself, so who knows?.

Originally Posted by zadigofla

UPDATE 3

So unfortunately the cat is clogged. The distributor was definitely the cause of the misfire but the sputtering (my main issue) was caused by all the back pressure from the cat. My mechanic said it was like trying to breathe while being strangled. He tested it without the upstream o2 sensors and said it ripped. We’re going to flex pipe it temporarily until I can afford a new cat. This Sunday I’ll be helping him install the new distributor.