For four-cylinder models, you pull the cable off the negative battery terminal, safely hoist the car on jackstands and then remove the starter motor. From the knock sensor, locate its electrical connector and de-pin it, proceed to remove the knock sensor retaining bolt and thereafter unbolt the knock sensor from the engine block tightening the bolt as you put in place the knock sensor. For the 2002 and 2003 v6 models turn off the engine by removing the negative battery terminal, remove the lugs nuts on the right front wheel and use the jack to raise the car on jack stands. Remove the knock sensor by disconnecting its electrical connector, then access the right inner fender splash shield, drivebelt and its tensioner, and the wiring to the alternator; move the wiring aside. The mounting bolt of knock sensor has to be unbolted and the sensor wires have to be disconnected from the clips and the bolt has to be tightened while assembling the knock sensor back again. As for the front sensor, the operation is almost identical, only you have to fasten a string to the knock sensor wiring harness to use it as a reference during the installation. The knock sensor is not accessible on the 2004 and later V6 models without removing the lower half of the intake manifold, but to check or change the knock sensor, unbolt the intake manifold and fuel rail assembly, and try to get to the knock sensor without removing the lower intake manifold. If so desired, remove the electrical connector from the knock sensor with the help of a socket and an extension, though it's better to tighten the sensor via the threads without the use of the thread sealant.