98s14se

First off, I have read the fuel injection bible, and searched for about 2 weeks now with no solid answer as of yet... Here is the issue... The car runs rich at all times, warm, cold, you name it. Does not smoke black. Smokes a little grey at times. Idles lopey as though it has a cam (it may for all I know, engine came from a racing zcar that was wrecked I'm told). Will idle ok, and drive for about 20 miles with new plugs. It will then foul the plugs and die will not start again for a few hours. Upon starting, it will barely idle, and will not run well enough to move more than a few feet. Replacing the plugs starts the cycle anew. Inspection of the plugs reveals a heavy gas smell, and heavy black carbon deposits from even 20 miles of use. I have done the following: Replaced all vacuum hoses and fuel lines with new (vehicle run so poorly at idle that even unplugging a large line has little to no effect). Replaced coolant temp sensor. Replaced wiring for coolant temp and coolant time sensors Unplugged coolant time, and coolant temp sensors both shile starting, and while running, when both hot, and cold. Both are operating as intended. Replaced coil and spark plug wires pulled fuel pressure regulator, and checked for blockages. Seems to be operating fine Replaced fuel filter Checked AFM for proper operation. Flapper moves correctly. Doubled checked routing of all vacuum lines. Lines are routed correctly. Blocked flow of fuel to cold start valve. No effect while warm or cold. Swapped ECU with another known good ECU. no effect. Replaced cap and rotor. No effect. Noted that distributor is loose. Moved distributor both counter and clockwise, and while some effect was felt as expected, nothing was corrected. Banged my head against the wall repeatedly, still with no effect :-P Here are a few things I was thinking: Cleaning the injectors or swapping them out with new. I'm thinking maybe poor atomization is causing the poor running condition and making it seem as though it is running rich. (the lack of black smoke makes me think this) Replace the AFM Aaaaannnnddd then I'm at a loss. Any ideas anyone?