Allante V8-273 4.5L (1991)
Fuel Pump Relay: Description and Operation
Fuel System Wiring Schematic
FUEL PUMP CONTROL
When the key is first turned "ON" (key in "RUN" position with engine "OFF"), the PCM will turn the fuel pump relay "ON" for two seconds. This builds
up the fuel pressure for cranking. If the engine is not started within two seconds, the PCM will shut the fuel pump "OFF" and wait until distributor
reference pulses are present. As soon as the engine is cranked, the PCM will turn the relay "ON" and "RUN" the fuel pump. The Oil pressure switch is
provided as a backup to the fuel pump relay.
The PCM will monitor the fuel pump circuit for proper operation and set the appropriate PCM code if necessary.
The PCM monitors voltage on the fuel pump power CKT 120 to detect fuel pump voltage supply faults.
