HELP - Suzuki engine not running right

[4x4rookie]

3 cylinder turbo 660cc engine only running on 2 cylinders
New spark plug and has spark
Can pull the lead out of distributor and no change to how engine runs so know which cylinder is effected.
So.....fuel related ? injector playing up ? or any other possible cause ?
Video of engine running at https://youtu.be/ZY16FXNoMR0
Any help appreciated
Cheers

[mercutio]

what sort of ignition system does it have is it dizzy or coil on plug etc

[4x4rookie]

hi
Dizzy so not individual coil packs.
Definitely a good spark at the plug
I pulled the 2 pin plug off the injector for the suspect cylinder and checked with an led light whether there was power and there is so now wonder if the injector is at fault, anyway of knowing without pulling it and replacing it ?
Any ideas as to other causes I may have missed ?
cheers

[mercutio]

how easy is it to swap the injectors if the prolem moves with the swap that is your problem