99 xcab z71 many problems

I bought this truck used with 130k on the odometer. I had if for 3 days and service engine soon light came on. I got five codes off of my code reader: Knock Sensor bank 2, bank 1 lean, bank 2 lean, multicylinder misfire, and something else. I have read several posts trying to see if anyone else had these same problems. I plan on tearing the intake manifold off this weekend to replace the knock sensor and the intake manifold gasket. Do you think there is anything else i need to do while i am pretending to be a mechanic?

sounds to me like your not getting enough fuel. im not sure if it would be a plugged fuel filter, bad or dirty injectors, or somethig else. wouldnt hurt to check everything over though while your working on it. try replacing the filter, they are only $6. i dont think you need to replace the knock sensor, it seems to be doin its job. see if the engine is starving for fuel it is going to run lean, leaner is hotter, hotter will cause detonation which will set off the knock sensor (exactly what its there for) which will result in a misfire.

may want to replace the fuel regulator too.