In his case probably neither because it isn't working.
You risk serious injury, blindness or even death by spraying diesel injectors as described. One good breath of the diesel oil vapour from an injector may cause permanent damage to your lungs, and there is NO WAY known to science to clear diesel oil or kerosene (which is actually worse) from lungs.
His problem is that his engine does not run.
Ergo it isn't spraying diesel at the injectors.
Reason is probably AIR in the system, or a failure or blockage of some sort in the injection pump.
But he took it off, so where do we go now?
CharlesY