2002 Express 5.7L Has Spark & Fuel / Will Not Start

I am working on a 2002 Chevrolet 3500 Express Van w/ a 5.7L Engine. A tune up was just last week, replacing spark plugs, wires, dist. cap, rotor button, air filter, and fuel filter. This morning, the van shut off while driving down the road, and now cranks but will not start. It keeps fouling the plugs. I have spark going to the plugs, and since they are fouling, I know I have fuel, but the engine will not start. I have since replaced the fuel pressure regulator for the fuel issue, no change. I have changed the ignition module, coil, crank sensor, and cam sensor, but still no change. Does anybody have any suggestions to look for next??? Any help would be greatly appreciated. :screwy:

You need spark,air,and fuel to run. Check for a restriction in the air inlet section of the engine. Does start and then shut down almost immediately?
If you can spray some starting fluid into the intake between the air flow meter and the engine. You can also check for a fouled up airflow meter.