You dont need to run a knock sensor, if you want you can connect 1 up but it'll run as normal without it, if the chip is set up for closed loop then you can fit 1 into the downpipe and use the existing wiring on the 4x4 loom, no need to change the wiring at the tps if its a 4x4 loom and l8, just change the tps to a pf09