Magnum V8-5.7L VIN H (2005)
Fuel Pressure: Testing and Inspection
Fuel Delivery Check
CHECKING THE FUEL DELIVERY SYSTEM
For the Engine circuit diagram Refer to SCHEMATICS AND DIAGRAMS.
Possible Causes
-
RESTRICTED FUEL SUPPLY LINE
-
FUEL PUMP INLET STRAINER PLUGGED
-
(N1) FUEL PUMP RELAY OUTPUT CIRCUIT OPEN
-
FUEL PUMP RELAY
-
FUEL PUMP
Diagnostic Test
1. FUEL PUMP OPERATION
Ignition on, engine not running.
With a scan tool, actuate the Fuel System test.
NOTE: It may be necessary to use a mechanics stethoscope in the next step.
Listen for fuel pump operation at the fuel tank.
CAUTION: Stop All Actuations.
Does the Fuel Pump operate?
Yes >> Go To 2
No >> Go To 6
2. FUEL PRESSURE
Turn the ignition off.
WARNING: The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose,
fitting or line, the fuel system pressure must be released. Failure to follow these instructions can result in personal injury or death.
Install a fuel pressure gauge at the engine. Ignition on, engine not running. With the scan tool, actuate the ASD Fuel System test and observe the
fuel pressure gauge.
NOTE: NOTE: Fuel pressure specification is 407 kPa ± 34 kPa (59 psi ± 5 psi).
CAUTION: Stop All Actuations.
Choose a conclusion that best matches your fuel pressure reading.
Below Specification
Go To 3
Within Specification
Test Complete.
Above Specification
Replace the fuel filter/fuel pressure regulator.
Perform (NGC) POWERTRAIN VERIFICATION TEST VER - 1.
3. RESTRICTED FUEL SUPPLY LINE
Turn the ignition off.
WARNING: The fuel system is under a constant pressure even with the engine off. Before testing or servicing any fuel system hose,
fitting or line, the fuel system pressure must be released.
Raise vehicle on hoist, and disconnect the fuel pressure line at the fuel pump module.
Install special tool #6539 (5/16) or #6631(3/8) fuel line adapter and the fuel pressure gauge between the fuel supply line and the fuel pump
module. Ignition on, engine not running.
With the scan tool, actuate the ASD Fuel System test and observe the fuel pressure gauge.
NOTE: Fuel pressure specification is 407 kPa ± 34 kPa (59 psi ± 5 psi).
CAUTION: Stop All Actuations.
Is the fuel pressure within specification now?
