Nissan frontier 3.3 knock sensor bypass where do you put the resistor?

underneath intake manifold between cylinder 1 and 2.

Bypassing (hotwiring) the knock sensor will remove a signal the computer needs to operate. Unexpected results for sure , possible damage to the computer may result. Replacing the knock sensor is the best way.

The pcm uses the knock sensor to monitor for engine knocking, and adjusts ignition timing based on this. If there is no knock sensor present, you will wind up with a hard fault that will keep the check engine lamp on continuously. Also, the truck will go into a more conservative driving mode to prevent knocking.
The knock sensor for a frontier is not terribly expensive, but it is a pain to access on nissan v6s, under the intake manifold

under intake

No you don't have to change the harness unless it is cracked, broken, or have burn marks.

no but the knock sensor does send a signal the ecm and it will ****** or advance the distributor timing

2.4 ENGINE TIME IS 3 HOURS 40 MINUTES THE 3.3 ENGINE 2 HOURS 20 MINUTES.

P0340....Camshaft Position Sensor 'A' Circuit (Bank 1 or Single Sensor)
P0325....Knock Sensor 1 Circuit (Bank 1 or Single Sensor)if you have no spark it your cam sensor

po325--ignition system or missfire.

Knock sensors can be difficult to locate because there usually buried under intake or exhaust manifolds and misc. engine wiring and plumbing. Knock sensors need to hear an engine knocking noise, therefore there usually located somewhere they can hear an engine knock. If it's a V6 then possibly it will be between the cylinder heads and access to them can only be attained by removing the intake manifold. I would suggest calling a Nissan Dealer parts person and ask them. Good luck.