All the messing with the fuel system may be of no consideration for this problem. Look carefully at those three wires at your distributor. One of these sends the "fire" order (for the injectors) to the ECU. If that signal is not getting through, the injectors won't inject, no matter how good your fuel pressure may be!

  Look not only at the connector, but at the wires near and at any bends. I lost my engine, in afternoon rush-hour traffic, because one of those three wires fatigued through, and broke. Inside the insulation, no less. It was not visible. My only clue (other than the dead engine) was the tach did not move, even during cranking. It should move a little, even on just the starter.

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Also, the plastic connector for the three wires coming out of the
distributor was cracked. Thinking I might have bumped the wires together
when replacing the regulator, I wrapped them back up with electrical tape.

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