Disconnect the cable from the negative battery terminal. For V6 engines, note that there are four CMP sensors, one for the intake camshaft and one for the exhaust on each cylinder head. Remove the engine cover. If removing the CMP sensors from the left side (Bank 2), take out the power steering reservoir. Disconnect the CMP sensor electrical connector, then remove the CMP sensor mounting bolt and the CMP sensor itself. Remove the CMP sensor O-ring and inspect its condition; if cracked, torn, or otherwise deteriorated, replace it. Lubricate the sensor O-ring with clean engine oil, and installation is the reverse of removal. For V8 engines, the sensor is located at the front of the engine, mounted on the timing chain cover. For L99 (VIN J) models, remove the water pump, then the alternator, followed by the alternator bracket mounting bolts and bracket. Remove the sensor and jumper harness assembly mounting bolts from the timing chain cover, disconnect the CMP sensor electrical connector and magnet connector, then remove the CMP sensor mounting bolt and the CMP sensor. Inspect the CMP sensor O-ring and replace it if necessary, lubricating it with clean engine oil before installation. For LS3 (VIN W) and LSA (VIN P) models, remove the drivebelts and idler pulley, then the alternator, followed by the bracket mounting bolts and bracket. Remove the sensor and jumper harness assembly mounting bolts from the timing chain cover, disconnect the engine harness electrical connector from the jumper harness connector, and then disconnect the sensor from the jumper harness connector. Inspect the CMP sensor O-ring and replace it if necessary, lubricating it with clean engine oil before installation.