Confusing injectors

[Pinkeric]

2013 1.8 TDCI T220
Ok so, I’m having a few issues at the moment. Main one is plumes of intermittent white smoke. Took it to a garage who said I’ve got air leaks throughout the engine, and injector 3 is dodgy. Oil and coolant levels seem to be stable so I don’t think head gasket is an issue. Hooked it up to Forscan and looked at the cylinder contributions, 1 and 2 were showing around .8 if I remember correctly, and 3 showing about 1.3 and 4 was showing around .6 So I bought a reconditioned injector, and changed the 3rd injector from the left, looking at the engine. 3 still showing the same, and I think 4 came up a bit but still lower than the others. So now I’ve just changed the second from the left, thinking they’re actually in firing order 1324, if that is the firing order. Seems to have brought cylinder 2 up to around 1, still smoking. I’ve attached the most recent forscan numbers.

So my questions:

1. Does cylinder 3 being higher than the rest mean it is dodgy and needs replacing?
2. Which one do I need to change, looking at the engine?
3. What do the cylinder contributions numbers actually represent?

I’m probably just going to get 2 more injectors and have the lot done anyway, but am I even looking at this right?
Starting to think the intermittent smoking is more due to the air leaks, which I think are from a previous owner changing the turbo and not replacing gaskets and tightening things up enough. I can already see one corrugated pipe with a bolt missing so air leaks are next on the list, but I would really like to understand what forscan is telling me about my injectors.

Thanks

[metalworker0]

i cant find explanation of cylbal readings and interpretation ..searched everywhere

here ..every time our resident expert "KNOBBY" is quoted figures with cylbal .he says do a leak off test to determine which injectors are not performing.

Another guy did the "learns" on forscan and they became closer at tick over

also each injector has to be coded if swapped around ....each new injector has to be coded

this is reading the code written on the side of the injector and typing it into forscan

i don't have forscan so cant tell you any more.


all the best.mark