another clicking problem

[Le_max]

So my engine was clicking a lot when I started it last weekend.
I ajusted the valves, they were off just a little (between .008 and .012 depending on the valve) I ajusted them perfectly to 0.010 when engine was cold.

There is some lound clicking coming out of the injector at constant speed (about 6 times per second when at 1000 rpm) ? The engine seems to miss some fire at idle.

Considering I was at 1000 rpm = 16 revolution per second = 8 explosion per second per cylinder. I could think that the clicking noise comes from ONLY one defect injector. How can I test this? I cant see how to unplug only one injector to see if the noise stops.

btw, I tried with a stetoscope ... could not isolate the sound

thanks.