[sprj8008]

I don't know what IBD system a '93 will be running and if the codes will appear. In OBDII the system monitors emissions systems. So you'll see a code if you've lost an O2 sensor or a major MAF miscalibration.

If you look at the process to set the timing, on my old toys, there is a bypass plug to drop the computer into a closed loop and allow you to set timing without influence of sensors and timing management. I might suggest you try this. Following that I'd start looking at mechanical issues.

I would suspect that the sensors were working properly so now that you have an issue I'd look other places first. I'd start with the connectors, making sure the sensors are connected securely and the engine and computer grounds are secure. Then I'd double check the timing alignment, which on a 22RE is a minor process. Then I'd get nervous, have a few beers and start looking at TPS, MAF and O2 sensors. An O2 sensor (the old style) might cause this as it won't show a proper mixture reading until it heats up.