Test Procedure

WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

HC1 CHECK THE SYSTEM INTEGRITY

Visually inspect the complete fuel delivery system for damage and leakage.
Check the following:
- fuel lines and connections
- relays
- fuel tank
- fuel pump
- fuel pressure regulator
- fuel pulse damper
- fuel rail at injectors
- damaged connector pins
- electrical connectors not fully engaged
Verify the vehicle has followed the maintenance schedule. A new fuel filter should have been installed within the last 48,280 km (30,000 miles).
Verify the IFS switch is set (button pushed in). Refer to the Owner's Literature for location.
Verify the fuse integrity.
Verify the 12-volt battery is fully charged.
Verify the fuel level, grade, and quality is sufficient to support normal operation of the engine.
Are any of the above concerns present?

Yes	No
REPAIR as necessary. CLEAR the DTCs. REPEAT the self-test.	GO to HC2.

HC2 CHECK ALL SYSTEM RELATED DEVICES (SENSOR, DAMPER, OR REGULATOR) FOR LEAKAGE

Key in OFF position.
FP connector connected.
Key ON, engine running.
Check for manifold vacuum at each system related component with a vacuum line.
Key in OFF position.
Wait 10 seconds.
Key ON, engine running.
Run the engine for approximately 10 seconds.
Key in OFF position.
Remove the vacuum hose on each system device connected to the fuel rail.
Inspect for the presence of fuel in the vacuum line of each device connected to the fuel rail.
Are all vacuum lines for system related devices indicating no fuel present?

Yes	No
GO to HC3.	If the vacuum line connected to a component indicates that a fuel leak is present, INSTALL a new component. CLEAR the DTCs. REPEAT the self-test.

HC3 CHECK THE FUEL PRESSURE

NOTE: During output state control, the fuel pump stays commanded on for only about 5 seconds.

Key in OFF position.
Relieve the fuel pressure. Refer to FUEL SYSTEM PRESSURE RELEASE .
Mechanical fuel pressure gauge connected.
Pressurize the fuel system. Refer to FUEL SYSTEM PRESSURE RELEASE .
Key ON, engine OFF.
Access the PCM and control the FP PID.
Control the FP ON.
Is the fuel pressure between 275-485 kPa (40-70 psi) ?

Yes	No
GO to HC6.	GO to HC4.

HC4 CHECK THE FUEL PUMP GROUND CIRCUIT FOR AN OPEN IN THE HARNESS

Key in OFF position.
FP connector disconnected.
Key ON, engine OFF.

Measure the voltage between:

( + ) Vehicle Battery	( - ) FP Connector, Harness Side
Positive terminal	FPGND

Is the voltage greater than 10 V?

Yes	No
GO to HC5.	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

HC5 CHECK THE FUEL PUMP POWER CIRCUIT FOR AN OPEN IN THE HARNESS

NOTE: During output state control, the fuel pump stays commanded on for only about 5 seconds.

Verify the IFS switch is set (button pushed in). Refer to the Owner's Literature for location.
FP connector disconnected.
Key ON, engine OFF.
Access the PCM and control the FP PID.
Control the FP ON.

Measure the voltage between:

( + ) FP Connector, Harness Side	( - ) Vehicle Battery
FPPWR	Negative terminal

Is the voltage greater than 10 V?

Yes	No
GO to HC6.	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

HC6 CHECK THE FUEL PRESSURE LEAKDOWN

NOTE: When the fuel pump is commanded off, the fuel pressure may substantially decrease and then stabilize.

NOTE: During output state control, the fuel pump stays commanded on for only about 5 seconds.

Mechanical fuel pressure gauge connected.
Key ON, engine OFF.
Access the PCM and control the FP PID.
Run the fuel pump to obtain maximum fuel pressure.
Command the fuel pump off.
Allow the fuel pressure to stabilize.
Monitor the fuel pressure for 1 minute.
Does the fuel pressure remain greater than 275 kPa (40 psi) after 1 minute?

Yes	No
GO to HC8.	GO to HC7.

HC7 CHECK FUEL INJECTOR FLOW AND LEAKAGE

NOTE: Observe the warnings, cautions, and notes at the beginning of this pinpoint test.

Check the fuel injectors for leakage and flow rate using the injector flow tester.
Are test results satisfactory?

Yes	No
GO to HC8.	INSTALL a new fuel injector as necessary. REFER to FUEL CHARGING AND CONTROLS - HYBRID . RESET the keep alive memory (KAM). REFER toRESETTING THE KEEP ALIVE MEMORY (KAM) . REPEAT the self-test.

HC8 COMPARE THE FRP PID TO THE MECHANICAL GAUGE

NOTE: Most mechanical gauges are referenced to atmospheric pressure. The fuel rail pressure and temperature (FRPT) sensor is referenced to manifold pressure. In order to make a valid comparison, the engine must be off.

NOTE: The vehicle may exhibit a long crank until the fuel system is pressurized.

Key in OFF position.
Relieve the fuel pressure. Refer to FUEL SYSTEM PRESSURE RELEASE .
Disable the fuel pump.
Key ON, engine OFF.
Monitor the mechanical gauge.
Access the PCM and monitor the FRP PID.
Compare the FRP PID value to the mechanical gauge.
Key in OFF position.
Pressurize the fuel system. Refer to FUEL SYSTEM PRESSURE RELEASE .
Key ON, engine running.
Allow the fuel pressure to stabilize.
Key in OFF position.
Key ON, engine OFF.
Compare the FRP PID value to the mechanical gauge.
Are the FRP PID values within 34 kPa (5 psi) of the mechanical gauge readings?

Yes	No
GO to HC9.	INSTALL a new FRPT sensor. REFER to the fuel system WARNING information at the beginning of this pinpoint test. REFER to ELECTRONIC ENGINE CONTROLS - HYBRID . CLEAR the DTCs. REPEAT the self-test.

HC9 CHECK THE FUEL SUPPLY LINE FOR RESTRICTION

NOTE: Observe the warnings, cautions, and notes at the beginning of this pinpoint test.

Disconnect the fuel supply line at the fuel rail.
Disconnect the fuel supply line at the fuel pump.
Check the fuel supply line for restriction.
Apply 21 to 34 kPa (3 to 5 psi) air pressure to the fuel supply line.
Does air flow freely through the line?

Yes	No
For misfire DTC diagnosis, GO to HD8. For symptoms without DTCs, RETURN to the SYMPTOM CHARTS article, Symptom Charts for further direction. For all others, INSTALL a new FP module. REFER to FUEL TANK AND LINES - HYBRID . CLEAR the DTCs. REPEAT the self-test.	REPAIR the cause of the restriction. CLEAR the DTCs. REPEAT the self-test.