240sx Running rich, somewhat solved?

[Pflynn]

Hey guys, best way to start this off is with a bit of a backstory I think...

I just purchased a *cheap* 240sx, thing was running super rich when I picked it up. I looked into it a tad and noticed that the previous owner had the ECU set to Diagnostics mode, as soon as I turned the dial back to regular "running" mode, the car s*** the bed and would idol awfully. I first noticed that the distributor was adjusted and had the timing totally retarded, I adjusted it to the middle, and tightened it down. Next, I noticed that the ground for the MAF had been modified(for some reason) and grounded really poorly, and that the cooling fan was wired to the reverse lights....I quickly fixed those two things and wired the fan straight to the ignition so that it would at least work, I started it and had the car running fairly decently again, no massive amounts of fuel dumping out of the back, no awful fuel smell and just an overall nice running car. I took it for a drive and after about 5 minutes the car started to backfire and pop and was just dumping fuel into its system again, I limped back to the shop, stalling and sputtering the whole way and decided to pull plugs. They were all black from the excessive amounts of fuel. I changed the plugs, changed the 02 sensor, which looked the same as well, changed the fuel filter and slammed in a MAF my friend had sitting around. Started it up, it started great, let it idol, it seemed happy...Drove it home and I had the exact same issue.

I've now just recently changed the Coolant Temp sensor and its running good but after about 40 minutes of driving, the car begins to overfuel and just cannon smoke out of the back, especially when stopped at a traffic light for a bit and I go to pull away. at one point it was shooting so much smoke out that my eyes were burning from all the fuel....My fuel economy is garbage, and has been since I've gotten the car, about 180km per half a tank(about 110miles), nothing like I've ever experienced before.

Any tips or leads would be greatly appreciated? I'm thinking it could possibly be the actual harness for the Coolant temp switch, the plug looks corroded and like crap, maybe I need to re-wire it somehow? Or possibly my ecu is shot? I haven't gotten a single check engine light the whole time I've been chasing these issues, just a code 5-5 twice.


TLDR
Car running rich when warm, excessive fuel, smoke coming out of tailpipe when stopped at a light and driving away
Replaced:
MAF
temp sensor
02
spark plugs
Fuel filter

[PapaSmurf2k3]

Yeah I'd try shaking the harnesses around the coolant temp sensor and TPS and MAF. If it stutters or idles up, you know you've got an issue there.