C350 petrol no power on cyl 1 2 and 3

[yorkiemark230]

Hi everyone. Any V6 gurus on here. Got a 2005 C350 petrol with no power on bank 1.
All 3 cylinders are sparking but i guess no fuel is getting there.
Any ideas ? Do these engine have seperate fuelling for each bank of the engine ? Do they have seperate throttle flaps etc , throttle motors etc .

 

[mioba]

Could simply be a air leak. did you read the codes yourself and come to your conclusion?

 

[yorkiemark230]

Could simply be a air leak. did you read the codes yourself and come to your conclusion?

All the codes are relevant to misfires detected etc.
All coilpacks are firing and all the plugs are firing. No power output from cylinders 1 , 2 and 3.
After searching Google I have got 3 possibilities. Harness break , Camshaft position sensor failure or maybe the dreaded balancer shaft.
Any other things anyone else can think of ?