5SFE suddenly running rough, 5SFE started running rough and now can barely run at all Options

[CosaChow]

Driving home from work the other day the car made a strange noise, possibly a backfire or something then started running real rough. A minute later the CEL came on (P0302). I did a tuneup, new plugs, wires, cap/rotor and if anything it ran worse. There was a small amount of oil in the distributor housing but nothing significant. Thanks to Richee3 for helping me continue troubleshoot we confirmed that we had spark on cylinder two, and the car ran the same with or without that plug wire connected. I then ran it for a minute with cylinder two plug removed to see if it was getting fuel. It seemed like it wasn't, so Richee3 kindly sent me an OEM fuel injector (plus some sweet chrome door strikers). Last night I swapped the injector and also replaced the valve cover gasket, spark plug tube gaskets, PCV valve and grommet. Unfortunately this hasn't helped the issue, it runs even rougher now and I can barely get it to idle for more than a second or two. I'm running out of ideas and may have to bite the bullet and get it towed to the shop. I thought I'd check here before doing that in a day or two. Any other thoughts on what could cause the issue?

[CosaChow]

The original code was a P0302 but I didn't check it after it was originally thrown as it wasn't running well enough to drive down to the parts store (I don't have my own reader).