The knock sensor for the four-cylinder models is located on the block just beside the starter motor. Start with raising the front side of the car and then placing it on stands that will help in holding it up. Remove the knock sensor wiring harness which is connected to the dipstick tube, unscrew the dipstick tube and take it out. Then ,you have to unscrew the electrical connector from knock sensor, unscrew the sensor retaining bolt and pull out the sensor. Installation is done in reverse order to removal while tightening of the mounting bolt is done to the required torque. On the V6 models, there are two knock sensors on the front side of the block, in the upper middle position, and close to the exhaust manifolds, thus they are of difficult access and require the car to be lifted. Jack up the vehicle and make certain it is supported firmly on jackstabs. If employed in the working on the rear sensor of 3.6L V6 engine, then you should take off the lower heat shield of the exhaust manifold. Disconnect the electrical connector from the sensor, then remove the nut and bolt, and the sensor. Just as with the four-cylinder models, installation is the reverse of removal, tightening of the mounting bolt to the correct torque is the last step.