Well i found my knock sensor code problem. Turns out the sensor was completely fine just chillin in the engine block, but there was no connection to it at all. The previous owner just cut it off. What would he gain by doing this? I had to go back where all the wires were and put in a new connector. What the hell would that connector be completely missing for?
Now, i still have an insufficient EGR flow code. No idea why, because i replaced the actual EGR itself, and checked all of the flow in and around the throttle body and nothing is stopping it at all.