Help with understanding DTC codes.

Question

I am getting several DTC codes for my 2000 Jaguar XJ8. P0010, P1000, P0332, P1384, P1642 and P1797. I understand that the P1000 can be a result of just having codes or changing out the battery. P1384 says that it could be the VVT solenoid which I change, oil flow to the VVT or malfunction of the VVT. Where and how do I check the oil pressure to the VVT. I have change the VVT and the component that houses the VVT. Do I need to change the VVT Actuator?

The P0332 says it it the knock sensor. Does this mean the knock sensor is bad or does it mean I am getting a knock in the engine? The P0010, I' not quite sure what the deal is with it.

The background is that when I press the accelerator the car has a tapping sound, so I changed the VVT because of the P1384 and mechanic told me it was the problem. I also changed the entire camshaft including the VVT. what else can I try to do resolve the tapping issue?

Thanks.