Hey all. I'm new here so go easy on me =)

I bought a 95 cavalier with a 94 engine in it and it's giving me troubles. A list of known issues with the car are:
- Engine fan doesn't work (a random blue wire activates fan when connected to positive on battery)
- Engine clicking (not a rod tap)
- Power steering pump & hose need replaced (power steering is currently drained and deactivated)
- OBD-II link doesn't connect with a reader
- Check engine light randomly turns on/off when driving
- A few electrical wire connectors and vaccum/pressure air hoses are laying dormant around the engine compartment, not connected


My main concern with the engine however, is the sputter in the engine when accelerating. When it sputters really bad, it backfires into the air intake manifold. I've tried to fix this by replacing the spark plugs & wires, fuel filter, and the catalytic converter. Would any of the previously mentioned problems be overlapping to cause a sputter like this?

I was thinking about just looking for a 95 engine somewhere and swapping it back in so I would have the right setup for the right vehicle, but I don't know if it would just slide right back into place or not.

Any kind of help or input would be much appreciated. Thanks!

Also, if it helps, the cavalier is a 2 door 2.2L (not the LS)