Mercury 225 EFI, Service Manual

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FUEL INJECTION
Page 3B-20 90-884294 OCTOBER 2001
EFI Fuel Management (High Pressure Fuel Route)
•
Perform low pressure checks before performing
checks on high pressure route.
•
Install fuel pressure gauge (P/N 91-852087A3) or
(P/N 91-881834A1) on to manifold pressure port.
•
Place ignition switch in “OFF” position 30 seconds
before testing.
•
Place ignition switch in “ON” position and note pres-
sure (41 to 45 psi; 283 to 310 kPa).
No or low fuel pressure Pump does not run
Fuel pressure above 45 psi (310 kPa)
Perform Final Filter Check Clogged or faulty fuel pressure
regulator remove and replace. Perform Electric Fuel Pump Volt-
age Test .
Final filter OK.
Final filter clogged.
Perform Fuel Pressure Regulator Test
.
Clean or replace final filter.
Steady stream of fuel [pressure
still below 41 psi (283 kPa).
Low or no fuel flow.
Replace fuel regulator.
Perform Electric Fuel Pump
Voltage Test .
Voltage from ECM driver circuit OK.
Low or inconsistent voltage
from ECM driver circuit.
Replace fuel pump. Replace ECM.
Results
Results
Results
Results
Results
Results
Perform pump inlet filter check
Inlet filter clogged.
Clean or replace final filter. Inlet filter OK.