Operation CHARM: Car repair manuals for everyone.
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

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Barometric Pressure Sensor: Description and Operation


The barometric pressure sensor is integrated within the ECA assembly. It detects atmospheric pressure and provides a signal to the ECA reflecting the altitude which the vehicle is operating. The ECA uses this information for the control of air/fuel ratio, idle speed, purge flow and ignition timing requirements.