Sorry for revive a old thread, but maybe a Helpful information for the next One: Yes They also Clicking
The Perfect way would be to send them someone who have a test rack. it isn't that expensive ( 1 Injektor 5 Pounds in Germany)
But you could also Test them if you get some Hoses and make you a test Rack with Bottles. Every Injector sprays in a Bottle. remove the sparks / Connector and let the starter Turn for Max 10 Seconds, 40-60 Sec Pause and then repeat till the Bottles are filled like 50 ml or whatever.
then Measure the weight and you can spot a little or a Big Difference.
The Problem on this way is you cant check if a Injector dies maybe in Higher Rev's that is only checkable in a test Rack.
If Someone think the Injectors doesn't Work fine, dont wait ! Send them to someone who can clean them. If a Injector decides to die, your engine are also gone =P
Greets
Juki