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Absolute Pressure Sensor: Description and Operation

DESCRIPTION
An absolute pressure sensor is mounted to the air cleaner housing. The sensor is used by the ECM to adjust for changes in altitude and for air intake obstructions due to a clogging air cleaner.

OPERATION
The ECM uses the intake air pressure sensor to monitor the intake pressure. Monitoring this pressure allows better control of the variable geometry turbocharger to suit the driving environment and preserve turbocharger durability.