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Position Sensor Replacement- Camshaft and Crankshaft

Bulletin 2003

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All vehicle applications that use camshaft and/or crankshaft position sensors


Camshaft and crankshaft position sensors identify the exact position of the camshaft and crankshaft during rotation to the powertrain control module (PCM). A camshaft or crankshaft sensor problem can cause many different drivability issues from a misfire to an engine no-start. The mechanical camshaft to crankshaft timing is maintained by a timing chain or belt to the cogs of the drive gears. If the mechanical cam to crank timing is misaligned for any reason a trouble code will set causing possible confusion during the diagnostic process. The mechanical timing could be off, yet the engine will run. Before replacing a sensor be certain the mechanical condition of the motor is in check.


Camshaft and crankshaft sensor signals must be synchronized to prevent a trouble code condition. Many vehicle applications require the sensors to be synchronized or relearned whenever a sensor is replaced, or the timing chain or belt are serviced. The service manual for your specific vehicle will provide information if this process needs to be performed. In some cases, this process may require the use of a full function scan tool as most code readers do not have the capability to perform this task. If the relearn procedure is not performed when needed, the PCM does not see the two sensors in time together and will set a diagnostic trouble code indicating the fault. Not performing this procedure may also create drivability concerns such as the computer detecting misfires that are not really occurring. This trouble code condition does not mean a part has failed or installed incorrectly, or that the engine is out of time, the trouble code is simply set to acknowledge a complete repair was not made and the code set criteria will not be eliminated until the relearn or synchronization process is completed.


After a thorough diagnosis to ensure that a camshaft or crankshaft position sensor are in fact the direct cause of the drivability or no-start condition, refer to the applicable service manual to aid in replacement of the sensor. Follow the correct installation process so that no damage will occur to any component during installation.

For addition support contact the GoTech technical services team at 855-207-5630 M-F 7:30-6:00 CST for assistance.

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