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Fuel Pump: Description and Operation

Fuel Pump Control
- When the ignition switch is initially turned on, the PCM supplies ground to the PGM-FI main relay that supplies current to the fuel pump for 2 seconds to pressurize the fuel system.
- When the engine is running, the PCM supplies ground to the PGM-FI main relay that supplies current to the fuel pump.
- When the engine is not running and the ignition is on, the PCM cuts ground to the PGM-FI main relay which cuts current to the fuel pump.