PINPOINT TEST HC: Fuel Delivery System: Introduction

WARNING: This page is about a different variant/trim than selected.

WARNING: THE FUEL SYSTEM REMAINS UNDER PRESSURE AFTER THE ENGINE IS OFF. RELIEVE PRESSURE BEFORE REPAIRING. HIGHLY FLAMMABLE MIXTURES ARE PRESENT. TO RELEASE PRESSURE FROM THE FUEL SYSTEM, CARRY OUT THE FOLLOWING:

CONNECT FUEL PRESSURE TEST KIT 310-D009 (D95L-7211A) OR EQUIVALENT.
GRADUALLY OPEN THE TESTING KIT VALVE TO RELIEVE THE FUEL PRESSURE IN THE VEHICLE FUEL SYSTEM AND DRAIN THE FUEL INTO A SUITABLE CONTAINER OR RETURN IT TO THE FUEL TANK.
TO AVOID UNNECESSARY FUEL SPILLAGE AND FIRE HAZARD, ANY TIME FUEL LINES ARE DISCONNECTED, THE IGNITION SWITCH MUST BE IN THE OFF POSITION UNLESS FUEL PUMP OPERATION IS REQUIRED FOR TEST PURPOSES.

FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.

WARNING: BEFORE WORKING ON OR DISCONNECTING ANY OF THE FUEL TUBES OR FUEL SYSTEM COMPONENTS, RELIEVE THE FUEL SYSTEM PRESSURE TO PREVENT ACCIDENTAL SPRAYING OF FUEL. FUEL IN THE FUEL SYSTEM REMAINS UNDER HIGH PRESSURE, EVEN WHEN THE ENGINE IS NOT RUNNING. FAILURE TO FOLLOW THIS INSTRUCTION MAY RESULT IN SERIOUS PERSONAL INJURY.

WARNING: DO NOT SMOKE, CARRY LIGHTED TOBACCO OR HAVE AN OPEN FLAME OF ANY TYPE WHEN WORKING ON OR NEAR ANY FUEL-RELATED COMPONENT. HIGHLY FLAMMABLE MIXTURES ARE ALWAYS PRESENT AND MAY BE IGNITED. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN SERIOUS PERSONAL INJURY.

WARNING: DO NOT CARRY PERSONAL ELECTRONIC DEVICES SUCH AS CELL PHONES, PAGERS OR AUDIO EQUIPMENT OF ANY TYPE WHEN WORKING ON OR NEAR ANY FUEL-RELATED COMPONENT. HIGHLY FLAMMABLE MIXTURES ARE ALWAYS PRESENT AND MAY BE IGNITED. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN SERIOUS PERSONAL INJURY.

WARNING: WHEN HANDLING FUEL, ALWAYS OBSERVE FUEL HANDLING PRECAUTIONS AND BE PREPARED IN THE EVENT OF FUEL SPILLAGE. SPILLED FUEL MAY BE IGNITED BY HOT VEHICLE COMPONENTS OR OTHER IGNITION SOURCES. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN SERIOUS PERSONAL INJURY.

WARNING: CLEAN ALL FUEL RESIDUE FROM THE ENGINE COMPARTMENT. IF NOT REMOVED, FUEL RESIDUE MAY IGNITE WHEN THE ENGINE IS RETURNED TO OPERATION. FAILURE TO FOLLOW THIS INSTRUCTION MAY RESULT IN SERIOUS PERSONAL INJURY.

NOTE: Replacement fuel injectors may not be the same color as the original injectors in the vehicle. Verify the replacement injector is correct for the application by part number.

This pinpoint test is intended to diagnose the following:

chassis components
engine vacuum
fuel pressure
fuel supply line
fuel supply
fuel filter (9155)
fuel injector(s) (9F593)
fuel pump (9H307)

NOTE: With the engine running, the FRP PID value may be higher than a fuel pressure reading taken with a mechanical gauge.

FUEL SYSTEM SPECIFICATION CHART (IGNITION ON, ENGINE OFF VALUES)

Application

Fuel System Type

FRP Or FLP PID Fuel Pressure (kPa)

FRP Or FLP PID Fuel Pressure (psi)

External Pressure Gauge (kPa)

External Pressure Gauge (psi)

Mustang 5.4L

ERFS ⁽¹⁾

240-485

35-70

240-485

35-70

Edge 2.0L, Explorer 2.0L, Focus

MRFS ⁽²⁾

331-485

48-70

331-485

48-70

All Others

MRFS ⁽²⁾

331-485

48-70

Fuel System Type Definitions:

⁽¹⁾

Electronic Returnless Fuel System (ERFS): This system does not incorporate a mechanical pressure regulator. Pressure is controlled by continuously varying the fuel pump speed through the fuel pump driver module (FPDM) or fuel pump control module. All vehicles equipped with ERFS use a fuel rail pressure temperature (FRPT) sensor.

⁽²⁾

Mechanical Returnless Fuel System (MRFS): Fuel pressure is controlled by a mechanical pressure regulator located on the fuel pump module in the fuel tank. Some vehicles use a fuel pump control module to control the fuel pump module at low and high speeds. Some GDI vehicles are equipped with a fuel pressure sensor that monitors low pressure fuel system pressure.

Inertia Fuel Shutoff (IFS) Switch - Reset Instructions

WARNING: IF YOU SEE OR SMELL GASOLINE AT ANY TIME OTHER THAN DURING FUELING, DO NOT RESET THE INERTIA FUEL SHUTOFF (IFS) SWITCH. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.

Key in OFF position.
Check for fuel leaks in the engine compartment.
If no leak is present, reset the IFS switch by pushing the reset button on the top of the switch. Refer to the Owner's Literature, Roadside Emergencies for the location of the IFS switch.
In the closed position, the button can be pressed an additional 1.57 mm (1/16 in) against a spring.
Key ON, engine OFF.
Key in OFF position.
Key ON, engine OFF.
Key in OFF position.
Check for leaking fuel.

Fig 1: Identifying Fuel Pump (FP) Connector
Courtesy of FORD MOTOR CO.