1986 740 GLE, B230F

I have a hot start issue and I just know that with these clues,you guys will be able to help me.

When it is cold it starts perfectly. The car will not start after it gets hot. If I kill the power to the main fuel pump, the car starts just fine. It idles perfectly but you cant even "blip" the throttle until you reconnect the pump or it will die.

I have tried replacing the following items with working units:
IAC valve (I have three but I don't trust any of them 100%), ECT sensor, Air Mass Meter, Fuel Injection Relay, Fuel Pressure Regulator, Distributor cap and rotor, and plug wires.

I have cleaned all ground points. I have rewired the entire harness under the hood. I have set base idle and timing. Throttle body is spotless. Throttle position sensor is set properly. Oxygen sensor is working. Hall sensor checks out OK (but could still be the problem, I guess). Plugs are clean. ECT is functioning properly.

I haven't cleaned the injectors but I did take them out and watch the spray patterns. I haven't checked the fuel pressure (But I have done the test to see that it IS flowing). I haven't adjusted the valve clearances. I haven't replaced any of the electroncs (not even the little one behind the airbox on the inner fender)

I had the hot start problem fixed for about three weeks. It started better than it ever had. The only problem was that it was stumbling at about 3-4000 rpms. It would jerk violently as the motor lost power. It felt like it was loosing spark or fuel. It also had little or no power throughout the RPM range.

One more thing....FUEL MILEAGE! I can only get around 10 MPG out of it no matter what I do. As you can see, I've been all over the car. I have replaced things, checked things, and cleaned things. LOTS of things. I still can't figure out why my MPG are so LOW.

Come on VOLVOnoids, don't let me down. I just know the answer is screaming in my face. I just can't seem to figure it out. Pleas help me.