Given that only one cylinder is involved, it is extremely unlikely (odds like getting hit by a comet while you sleep tonight :-) ) that is is anything generic such as the crankshaft sensor. Whatever the problem is, it must be limited to one cylinder. So that basically eliminates any global systems such as crankshaft sensor, camshaft sensor (there are two), variable valve timing, etc., etc. What we are left with is things unique to one cylinder which are the valves of course (unlikely IMO), or the ignition system or the induction system. If you have swapped the ignition coil (stick coil) and spark plug, and the problem stayed with the original cylinder, it is HIGHLY unlikely that the problem is with the ignition system (assuming of course that you also swapped the coil to harness connections. That leaves induction: air is supplied through the throttle body via a universal throttle rod and individual throttle bodies. So unless that rod suddenly broke, air should not be the problem. That leaves, by default, the injector, which is unique to each cylinder. Fuel injector failures are not uncommon adn that could very well be the cause of the problem.
The diagnostic test only confirms that there is a fuel injection coil connected to the ECU, not that the valve actually opened and is shipping fuel. Again, fuel injection clogging / failure is a known failure method although not common, it does happen. And it would perfectly explain what is happening with your C-14.
Unfortunately, the easiest tests are not all that easy due to fuel injector access. No. 1 is no problem but No. 2 (Easy Boys) is quite a bit more difficult. Still, I think this is the likely cause of your cylinder failure given your posts and the data I have to work with. Sorry to be the bearer of bad news....
Brian
I have the KDS. And the inyectors test were fine !!!!!
Do not show any problem.
I read in other forum something about the Crankshaft sensor, but i'm not sure
because the problem only affect one cylinder.