Unfortunately there isn't really enough information to give a good diagnosis. The computer on a 93 isn't very sophisticated so don't expect that to answer all your questions. It is possible that you have low fuel pressure since the fuel filter change helped. I wouldn't think it was the catalytic converter. That's an emissions component. Unless it's completely clogged it won't negatively affect performance. You could buy a chiltons/haynes and start buying tools and going through systems and troubleshooting your way to a solution. If that sounds good to you then go for it, you'll learn alot and the forums are your friend. The fact that it was fine then suddenly wasn't sounds like a solenoid or electrical issue. If you absolutely need to drive the thing right now, take it to get worked on somewhere you trust. Sent from my SM-G975U using Tapatalk