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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Fuel Pressure Control Module: Description and Operation

Fuel Module:





On heavy duty models, a fuel module will override the ECM two second timer and the fuel pump will run for twenty seconds and then shut OFF if the vehicle is not started. This circuit corrects a hot restart (vapor lock) during a high ambient temperature condition. Refer to COMPONENT LOCATIONS/UNDERHOOD BLOCK DIAGRAM for under hood general location.