The CMP sensor provides the camshaft position information, called the CMP signal, which is used by the Powertrain Control Module (PCM) for fuel synchronization. On 2 wire Sensor engines, the distributor stator or Camshaft Position (CMP) sensor is a single Hall effect magnetic switch. This is activated by a single vane, and is driven by the camshaft.
On Three Wire Sensor engines, the Camshaft Position (CMP) sensor is a variable reluctance sensor, which is triggered by the high-point mark on one of the camshaft sprockets.The Distributor engine does not use a separate CMP sensor. It utilizes a conventional distributor, equipped with a Hall effect device, for this function.
The following symptoms can be caused by intermittent wiring connections or faulty signal to the EMS.
Using a Digital Volt-Ohmmeter (DVOM) set to the voltage function (scale set to monitor less than 5 volts), measure the voltage between break-out box terminals 24 and 46 with the engine running at varying RPM. If the voltage reading varies more than 0.1 volt AC, the sensor is okay.
REMOVAL & INSTALLATION
NOTE: Prior to removing the camshaft position sensor, set the No. 1 cylinder to 10°After Top Dead Center (ATDC) of the compression stroke. Note the position of the sensor's electrical connection. When installing the sensor, the connection must be in the exact same position.
NOTE: The oil pump intermediate shaft should be removed with the camshaft sensor housing.
NOTE: The cover tool should be square and in contact with the entire top surface of the camshaft position sensor housing.
If the sensor connector is positioned correctly, DO NOT reposition the connector by rotating the sensor housing. This will result in the fuel system being out of time with the engine. This could possibly cause engine damage. Remove the sensor housing and repeat the installation procedure beginning with Step 1.
A camshaft is a shaft to which a cam is fastened or of which a cam forms an integral part.(source wiki)What do Camshafts do?
Inside an engine are valves that open and close to allow fuel in and exhaust out of each cylinder. The rotation of the camshaft is what determines when the valves open and close. It is important to have the camshaft timing perfect. The camshaft has a sensor that tells the engines computer when to spray fuel from the injector so that it happens at the same time the intake valve is opened by the camshaft