On Board Diagnostics II PCED

1999 PCED On Board Diagnostics II

SECTION 5: Pinpoint Tests

HC: Fuel Delivery System

HC1 CHECK SYSTEM INTEGRITY

Visually inspect the complete fuel delivery system for damage; including fuel lines, connections, relays, fuel tank, fuel pump, fuel pressure regulator, fuel pulse damper and fuel injector areas for leaks, looseness, cracks, kinks, pinching, or abrasion caused by a collision or mishandling.
Visually inspect electrical harness and connectors for loose pins, corrosion, abrasion, or other damage from collision or mishandling.
Check electrical connectors for proper mating.
Verify vehicle has followed maintenance schedule.
Verify inertia fuel shutoff (IFS) switch is set.
Verify battery is fully charged (12.5 volts or greater).
Verify electrical/fuse integrity.
Verify fuel level in the tank is sufficient.

Has any concern been found?

Yes	No
REPAIR as necessary.	GO to HC2 .

HC2 CHECK VOLTAGE AT FUEL PUMP HARNESS CONNECTOR

Connect battery charger.
Verify IFS switch state. Follow the IFS switch reset procedure at the beginning of this pinpoint test.
Disconnect the fuel pump harness connector at the fuel pump.
Key on, engine off.
Connect a digital multimeter between the fuel pump power circuit and fuel pump ground circuit at the fuel pump harness connector (refer to the Wiring Diagram Manual for correct pin location).
Access Output Test Mode (refer to Section 2 ) and turn on the fuel pump circuit and monitor the voltage reading.

Was the voltage greater that 12.5 volts?

Yes	No
KEY OFF. EXIT Output Test Mode. RECONNECT fuel pump harness connector. GO to HC3 .	KEY OFF. FOR vehicles with electronic returnless fuel systems: GO to Pinpoint Test Step KB70 . ALL others: CHECK for opens and shorts in the fuel pump power and ground circuits.

HC3 CHECK FUEL FILTER FOR PROPER MAINTENANCE

Locate and inspect the vehicle maintenance schedule and fuel filter. Check for last repair date.

Was the fuel filter replaced within the last 48,280 km/30,000 miles?

Yes	No
GO to HC4 .	REPLACE fuel filter. GO to HC4 .

HC4 CHECK FUEL PRESSURE

WARNING: BEFORE SERVICING OR REPLACING ANY COMPONENTS IN THE FUEL SYSTEM, REDUCE THE POSSIBILITY OF INJURY OR FIRE BY FOLLOWING DIRECTIONS IN FUEL SYSTEM CAUTION, HANDLING AND WARNING AT THE BEGINNING OF THIS PINPOINT TEST.

Install fuel pressure tester.
Release fuel pressure.
Key on, engine off.
Access Output Test Mode and run the fuel pump to obtain maximum fuel pressure.

Note: The fuel pump will only operate for approximately 8 seconds when Output Test Mode is selected and activated.

Vehicle	kPa	psi
Contour/Mystique, Cougar 2.5L	310-415	45-60
Continental	310-415	45-60
Escort/Tracer, Mustang LS6/LS8	240-380	35-55
Ranger	386-496	56-72
Ranger (Flex Fuel)	380-517	55-75
All Others	207-310	30-45

Is the fuel pressure at the specified pressure (use the fuel pressure chart)?

Yes	No
KEY OFF. For Electronic/Mechanical Returnless Fuel Systems : GO to HC12 . All others: GO to HC5 .	KEY OFF. For Mechanical Returnless Fuel System with fuel pressure greater that 448 kPa (65 psi). REPLACE fuel pressure regulator in fuel tank. For Mechanical Returnless Fuel System with fuel pressure less than 310 kPa (45 psi): GO to HC6 . For Electronic Returnless systems with fuel pressure less than 517 kPa (75 psi). GO to HC13 . For Electronic Returnless systems with fuel pressure greater than 862 kPa (125 psi). Concern is elsewhere. RETURN to Section 3 , Symptom Charts for further direction. All others: Fuel pressure greater than 280 kPa (40 psi) (Contour/Mystique, Cougar 415 kPa (60 psi) on returnable fuel systems , GO to HC10 . Fuel pressure less than 240 kPa (35 psi) (Contour/Mystique, Cougar 310 kPa (45 psi) on returnable fuel systems , GO to HC13 .

Yes

KEY OFF. For Electronic/Mechanical Returnless Fuel Systems : GO to HC12 .

All others: GO to HC5 .

KEY OFF. For Mechanical Returnless Fuel System with fuel pressure greater that 448 kPa (65 psi). REPLACE fuel pressure regulator in fuel tank.

For Mechanical Returnless Fuel System with fuel pressure less than 310 kPa (45 psi): GO to HC6 .

For Electronic Returnless systems with fuel pressure less than 517 kPa (75 psi). GO to HC13 .

For Electronic Returnless systems with fuel pressure greater than 862 kPa (125 psi). Concern is elsewhere. RETURN to Section 3 , Symptom Charts for further direction.

All others:

Fuel pressure greater than 280 kPa (40 psi) (Contour/Mystique, Cougar 415 kPa (60 psi) on returnable fuel systems , GO to HC10 .

Fuel pressure less than 240 kPa (35 psi) (Contour/Mystique, Cougar 310 kPa (45 psi) on returnable fuel systems , GO to HC13 .

HC5 CHECK FUEL PRESSURE LEAKDOWN

Observe Warning, Caution and Notes.
Fuel pressure tester installed.
Key on, engine off.
Access Output Test Mode and run the fuel pump to obtain maximum fuel pressure.
Key off.
Verify fuel pressure remains within 34 kPa (5 psi) of the maximum fuel pressure for 1 minute after the fuel pump is turned off.

Does the fuel pressure remain within 34 kPa (5 psi)?

Yes	No
GO to HC7 .	GO to HC6 .

HC6 CHECK PRESSURE REGULATOR AND PULSE DAMPER DIAPHRAGM

Fuel pressure tester installed.
Start engine and run engine for 10 seconds.
Key off, wait 10 seconds.
Start engine and run engine for 10 seconds.
Key off, remove vacuum hose from fuel pressure regulator or pulse damper port.
Inspect for fuel in the vacuum hose or regulator port or pulse damper.

Is the vacuum hose and regulator or pulse damper port free of fuel?

Yes	No
GO to HC12 .	REPLACE fuel pressure regulator. For Mechanical Returnless Fuel System: Replace pulse damper.

HC7 CHECK FUEL PRESSURE, ENGINE RUNNING

Fuel pressure tester installed.
Disconnect vacuum hose at the fuel pressure regulator and plug it.
Drive vehicle with heavy accelerations while observing fuel pressure gauge reading.

Does fuel pressure reading hold steady within 21 kPa (3 psi) during test?

Yes	No
GO to HC8 .	GO to HC13 .

HC8 CHECK FUEL PRESSURE REGULATOR RESPONSE

Fuel pressure tester installed.
Install vacuum gauge to intake manifold.
Start engine and observe both gauges.
Accelerate and decelerate engine speed to vary vacuum gauge reading.

Does the fuel pressure gauge reading increase as vacuum gauge reading decreases or decrease as vacuum gauge reading increase?

Yes	No
Concern is elsewhere. RETURN to Section 3 , Symptom Charts for further direction.	GO to HC9 .

HC9 CHECK VACUUM SUPPLY

Fuel pressure tester installed.
Vacuum hose disconnected and plugged at the fuel pressure regulator.
Install a hand held vacuum pump to the fuel pressure regulator.
Start engine, remain at idle.
Observe fuel pressure while applying vacuum.

Does the fuel pressure change as the vacuum changes?

Yes	No
REPAIR vacuum source.	REPLACE fuel pressure regulator.

HC10 CHECK FOR RESTRICTED FUEL RETURN LINE

Fuel pressure tester installed.
Remove fuel return line at the fuel rail and connect a short hose from the fuel rail to a measure container of at least 1.1 liter (1.0 quart) capacity.
Key on, engine off.
Access Output Test Mode and run the fuel pump to obtain maximum fuel flow (one cycle of the fuel pump is all that is required).
Record fuel pressure and observe if fuel is being returned to the measuring container.

Is fuel pressure between (Contour/Mystique, 2.5L Cougar 310 and 415 kPa (45 and 60 psi) or 240 and 280 kPa (35 and 40 psi) on all others and is fuel returning to the container?

Yes	No
KEY OFF. GO to HC11 .	KEY OFF. Fuel pressure greater than 415 kPa (60 psi) on Contour/Mystique, 2.5L Cougar or all others 290 kPa (45 psi). REPLACE fuel pressure regulator.

HC11 CHECK FUEL RETURN SYSTEM

Observe Warning, Caution and Handling at the beginning of this pinpoint test.
Disconnect fuel return line at the fuel rail.
Disconnect fuel return line at the fuel pump.
Check the fuel return line for restrictions due to blockage, kinking or pinching.
Apply 21 to 34 kPa (3 to 5 psi) regulated shop air to the return line pressure.

Does air flow freely through the line?

Yes	No
REPLACE the fuel pump module.	REPAIR the fuel return line.

HC12 CHECK FUEL INJECTOR FLOW AND LEAKAGE

Observe Warning, Caution and Handling at the beginning of this pinpoint test.
Check injectors for leakage and flow rate: Use SBDS.

Is the SBDS test results satisfactory?

Yes	No
For symptoms without DTCs and Electronic/Mechanical Returnless Fuel Systems: RETURN to Section 3 , Symptom Charts for further direction. All others: VERIFY no other leak exists. REPLACE fuel pump module.	REPLACE the failed fuel injector(s).

HC13 CHECK FUEL SUPPLY LINE FOR RESTRICTION

Observe Warning, Cautions and Handling at the beginning of this pinpoint test.
Disconnect fuel supply line at the fuel rail.
Disconnect fuel supply line at the fuel pump.
Check the fuel supply line for restrictions due to blockage, kinking, or pinching.
Apply 21 to 34 kPa (3 to 5 psi) regulated shop air pressure to the supply line.

Does air flow freely through the line?

Yes	No
Air flows freely. REPLACE fuel pump module.	REPAIR cause of restriction.