Manuals through 2025 now available!

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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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Main Relay (Computer/Fuel System): Description and Operation

PGM-FI Main Relay

The PGM-FI main relay contains two separate relays. One is energized whenever the ignition is ON to supply battery voltage to the ECM, power to the fuel injectors, and power for the PGM-FI relay (FUEL PUMP). The PGM-FI relay (FUEL PUMP) is energized to supply power to the fuel pump for 2 seconds when the ignition is switched ON (II), and when the engine is running.