I solved a similar issue by soaking the pipe holders in brake fluid for a week. The pipe holder is the piece that is removed on #1 to do the injection timing. Go ahead and pull each connection with the associated spring and plunger element and soak them. You'll not that the pipe connection has a tiny orifice. There is actually a spring type device inside that helps to avoid secondary combustion from the fuel shock wave traveling back down the injector line after the injector closes, (Or something like that).

At any rate, the orifice is quite small in diameter and any clogging here will affect idle quality.
Mike