The pattern should be a broad spray, more of a mist than a stream. I cleaned
mine yesterday as part of a hose and seal replacement job. Only one of the
12 began as a stream and I was able to clean that one so that a mist was
output in short order. Here is the method I used. I used a spray can
carburetor cleaner. The red tube was attached, the end wrapped in tape to
closely fit a vacuum accessory cone-shaped piece that allowed the tube to
seal into the fuel injection hose attached to the injector. My daughter then
activated the cleaner as I applied 12 volts to the injector. (By the way,
the injectors were from a 78 XJ12 and 4 volts or less didn’t move the
solenoid. In any event, I only did a few short bursts.
Come to think of it, how are you testing yours? I think that you will have
to build fairly strong pressure to get the mist you desire – Something like
the 27-30 lbs. of the fuel line? Please let me know if I can be of any help.