Fuel Pump: Description and Operation

Fuel Pump Control
When the ignition is turned ON (II), the ECM grounds the PGM-FI main relay which feeds current to the fuel pump for 2 seconds to pressurize the fuel system. With the engine running, the ECM grounds the PGM-FI main relay and feeds current to the fuel pump. When the engine is not running and the ignition is ON (II), the ECM cuts ground to the PGM-FI main relay which cuts current to the fuel pump.