Dist cap and plug wires are brand new.

I would have thought that when you unplug the injector and see no change, that the problem is isolated to fuel. Thinking about it further I see that if no spark is present, removing the fuel will have no effect.

I can repeat the test by pulling the plug wire and seeing if I get the same effect - although the reverse is now true - removing spark when no fuel is present will have no effect.

Wiring harness has been replaced.

I'll pull the plug and see what I find. Maybe there's a piece of crap on it that is causing misfire until everything gets a little warm.

Regardless - it couldn't hurt to run some injector cleaner through, right? I'm thinking fuel-rail administered systems - not through the tank stuff like Techron.

Any suggestions?