Vibe 2003-2005

Camshaft Position Sensor Actuator



The Camshaft Position (CMP) actuator system enables the Powertrain Control Module (PCM) to change the intake camshaft timing while the engine is running. The CMP actuator solenoid controls the advance or retard of the camshaft. The CMP actuator solenoid is controlled by a pulse width modulated (PWM) signal from the PCM. The CMP sensor monitors the camshaft position or the camshaft angle, and compares that position or phase to the Crankshaft Position (CKP) sensor signal. The PCM determines whether the camshaft angle is correct by comparing the actual camshaft position to the target camshaft position. By continuously analyzing the input of the CMP sensor and the CKP sensor the PCM can detect a failure in the CMP actuator system.

Removal & Installation

  1. Remove the engine cover.
  3. Disconnect the electrical connector from the CMP actuator solenoid valve.
  5. Remove the fastener retaining the CMP actuator solenoid valve from the cylinder head.
  7. Remove the CMP actuator solenoid valve and the O-ring from the cylinder head.

To install:

  1. Installation is the reverse of removal. Make sure to use a new O-ring.


  1. Check the condition of the connector. Make sure the connector is firmly attached. Check for broken or bent connector pins. Repair any connector damage before continuing with troubleshooting the issue.
  3. Check the condition of the wiring to the connector. If the wiring is damaged, repair the wiring before continuing with any further tests.
  5. Turn OFF the ignition.
  7. Remove the CMP actuator solenoid.
  9. Connect the CMP actuator solenoid to B+ and to ground with a pair of fused jumper wires.
  11. Observe the movement of the solenoid plunger when electrical power is applied and released.
  13. The solenoid plunger must extend to at least 0.125 inches when voltage is applied and then retract when voltage is removed. If not, replace the actuator.

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    Fig. Camshaft Position (CMP) actuator solenoid terminals; (1) CMP Actuator High Control, (2) CMP Actuator Low Control