Took my turbo and manifold off the other day for repair- the exhaust port from pot 2 is quite a pale colour compared to the other 3 (black)...
Weird thing is that when i remove the spark plugs they all look the same- no colour difference
Should i be worried?
If its running lean i think it could be either

1. Injector
2. Kinked injector pipe
3. Metering head not distributing correctly

Anyone had this kind of problem themselves or know the most likely cause?

Any advice would be greatly appreciated!