I would think you'd be having troubles under load or heavy accelaration if the injector wasn't supplying enough fuel.
You said the one injector... isn't it multi-port? How are the other inj's?
How long has this been going on? Maybe contaminated fuel, or water in fuel?
How much is in the tank?
The other thing to do is check the actual voltage at the injectors, but pulse width and duration are just as important.
Is the fuel tank venting? I've seen tanks develope enough suction to draw the fuel out of the lines and the pumps causing an excessive amount of cranking to get the fuel back to the rail.
I'd take the return fuel line off and pump some of the fuel out and check it.
I'd also use that fuel in an atomizer or spray bottle instead of Quick Start. That stuff can be nasty, even to non-diesels.