Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Barometric Pressure Sensor: Description and Operation

PURPOSE
Detects changes in atmospheric pressure related to changes in altitude from sea level.

LOCATION
Integral with PCME.

OPERATION
As the vehicle changes altitude, air/fuel ratio adjustments are necessary to maintain good driveability and low emissions. PCME uses input from this sensor to make needed adjustments.