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Test HC: Fuel Delivery System: Testing

  1. 1) Check System Integrity

    Turn ignition off. Inspect fuel system for leaks, damaged, kinked or cracked hoses. Inspect wiring harness for damage or loose connectors. Ensure battery is fully charged and fuses are okay. If vehicle does not start, ensure vehicle has sufficient fuel in the fuel tank and that Inertia Fuel Shutoff (IFS) switch is not tripped. Repair or replace as necessary. If no faults are found, go to next step.
    2. WARNING: Before performing this test step, release fuel system pressure to reduce risk of injury or fire. See FUEL SYSTEM PRESSURE RELEASE under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - VILLAGER article.

  2. 2) Check Fuel Pressure
    Turn ignition off. Install fuel pressure gauge in fuel line between fuel filter and fuel rail. Turn ignition on, engine off. Record fuel pressure. Start engine and record fuel pressure. If fuel pressure is about 43 psi (294 kPa) with ignition on, engine off and about 34 psi (234 kPa) with engine running, go to step  40). If fuel pressure is zero, go to next step. If fuel pressure is low, go to step  20). If fuel pressure is high, go to step  30).

  3. 3) Check Voltage To Fuel Pump Relay

    Turn ignition off. Disconnect fuel pump assembly connector at fuel pump. Turn ignition on. Using DVOM, measure voltage between chassis ground and fuel pump harness connector terminal No. 2 (Light Green/Red wire) within 5 seconds of turning ignition on. See Figure. If voltage is more than 10 volts, go to step  9). If voltage is 10 volts or less, go to next step.

  4. 4) Check Power Supply To Fuel Pump Relay

    Turn ignition off. Remove fuel pump relay from left side engine compartment relay block. See Figure. Turn ignition on. Using DVOM, measure voltage between chassis ground and fuel pump relay cavities No. 1 and 3 (Black/Red wires). If voltage is more than 10 volts, leave fuel pump relay removed and go to next step. If voltage is 10 volts or less, check FUEL PUMP fuse (15-amp) and RELAYS fuse (10-amp). If fuse(s) is blown, replace as necessary. If fuse repeatedly blows, repair appropriate power Black/Red wire for short to ground. If fuse(s) is okay, repair open in appropriate Black/Red wire. See WIRING DIAGRAMS article.

  5. 5) Check Fuel Pump Relay

    Connect a jumper wire between battery power to fuel pump relay terminal No. 1. Connect another jumper wire between negative battery terminal and fuel pump relay terminal No. 2. Using DVOM, measure resistance between relay terminals No. 3 and 5. See Figure. Resistance should be less than 5 ohms. Remove jumper wires. Resistance between terminals No. 3 and 5 should now be more than 10 k/ohms. If either resistance is not as specified, replace fuel pump relay and go to step  2). If both resistances are as specified, go to next step.

  6. 6) Check Continuity Of Fuel Pump Relay Circuits To PCM

    Ensure ignition is off. Disconnect PCM harness connector. Inspect connector for damaged pins and repair if necessary. Using DVOM, measure resistance of FPR circuit (Blue/Red wire) between fuel pump relay cavity No. 2 and PCM harness connector terminal No. 11. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Blue/Red wire. See WIRING DIAGRAMS article.

  7. 7) Check For Open To Fuel Pump

    Ensure fuel pump relay is removed and fuel pump assembly connector is disconnected. Using DVOM, measure resistance of Light Green/Red wire between fuel pump harness connector terminal No. 2 and fuel pump relay cavity No. 5. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Light Green/Red wire between fuel pump relay and fuel pump assembly.
    8. NOTE: Ensure IFS switch is not tripped. Reset IFS switch if necessary.

  8. 8) Check For Short(s)
    Ensure fuel pump assembly and PCM are disconnected and fuel pump relay is removed. Using DVOM, measure resistance between chassis ground and fuel pump relay cavity No. 5 (Light Green/Red wire). Using DVOM, measure resistance between fuel pump relay cavity No. 2 (Blue/Red wire) and cavities No. 1 and 3 (Black/Red wires). See Figure. If resistances are more than 10 k/ohms, replace PCM. If resistance is 10 k/ohms or less, repair short to ground or between circuit(s). See WIRING DIAGRAMS article.

  9. 9) Check Fuel Pump Assembly

    Ensure fuel pump module assembly is disconnected. Using DVOM, measure resistance between fuel pump assembly connector terminal No. 3 (Black/White wire) and No. 2 (Light Green/Red wire). See Figure. If resistance is .2-5.0 ohms, go to next step. If resistance is not .2-5.0 ohms, replace fuel pump assembly.

  10. 10) Check Fuel Pump Ground

    Using DVOM, measure resistance between chassis ground and fuel pump assembly harness connector terminal No. 3 (Black/White wire). If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, go to step  13).

  11. 11) Check Inertia Fuel Shutoff Switch

    Disconnect and remove Inertia Fuel Shutoff (IFS) switch. Vigorously shake IFS switch to ensure switch trips. Using DVOM, measure resistance between IFS switch harness connector terminal No. 2 (Black wire) and No. 3 (Black/White wire) with IFS switch "Tripped" and "Set". See IFS SWITCH TESTING  table. See Figure. If resistances are as specified and switch trips when shaken, go to next step. If resistances are not as specified or switch does not trip when shaken, replace IFS switch.

  12. 12) Check IFS Switch Ground

    Using DVOM, measure resistance between chassis ground and IFS harness connector terminal No. 2 (Black wire). If resistance is 5 ohms or more, repair open in Black wire. If resistance is less than 5 ohms, repair open in Black/White wire between IFS switch and fuel pump. See WIRING DIAGRAMS article.
    13. WARNING: Before performing this test step, release fuel system pressure to reduce risk of injury or fire. See FUEL SYSTEM PRESSURE RELEASE under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - VILLAGER article.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 13) to step 20). No test procedures have been omitted.

  13. 13) Check Fuel Pump Motor
    Reconnect all electrical connections. Connect a fuel pressure gauge to fuel filter. Turn ignition on and off 3 times allowing 5 seconds between ignition cycles. If maximum fuel pressure is 43 psi (294 kPa), go to step  21). If fuel pressure is less than 43 psi (294 kPa), replace fuel pump.

  14. 20) Check Power Supply To Fuel Pump

    Turn ignition off. Disconnect fuel pump harness connector. Turn ignition on. Using DVOM, measure voltage between chassis ground and fuel pump assembly harness connector terminal No. 2 (Light Green/Red wire). See Figure. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, go to step  3).
    15. WARNING: Release fuel system pressure to reduce risk of injury or fire. See FUEL SYSTEM PRESSURE RELEASE under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - VILLAGER article.

  15. 21) Check In-Line Fuel Filter Condition
    Release fuel system pressure. Remove high pressure in-line fuel filter for inspection. Inspect filter element for contamination or blockage. Compare customer's service record and driving conditions versus recommended maintenance schedule. Replace filter if necessary. If fuel filter is free of contamination, blockage, and within recommended maintenance schedule, go to next step.

  16. 22) Check Fuel Pressure Regulator Condition

    Ensure fuel system pressure has been released. Install fuel pressure gauge in fuel line between fuel filter and fuel rail. Start engine and operate for 10 seconds. Turn ignition off and wait 10 seconds. Start engine again and operate for 10 seconds. Turn ignition off. Disconnect vacuum hose from fuel pressure regulator. Inspect vacuum port in pressure regulator for evidence of fuel leakage through diaphagm. If hose or vacuum port are wet with fuel, replace fuel pressure regulator. If hose and vacuum port are dry, connect a vacuum pump to port on pressure regulator and apply 20 in. Hg of vacuum. If fuel pressure decreases when vacuum is applied, go to next step. If fuel pressure does not change, replace fuel pressure regulator and go to step  2).
    17. WARNING: Release fuel system pressure to reduce risk of injury or fire. See FUEL SYSTEM PRESSURE RELEASE under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - VILLAGER article.

  17. 23) Check Fuel Pump Flow Volume
    Release fuel system pressure. Disconnect fuel line between fuel filter and fuel rail. Connect a hose to fuel filter and then place other end of hose into a measuring container that is inside an empty overflow container. Turn ignition on. Fuel pump will run for 5 seconds. Collect fuel in measuring container for 5 seconds. Turn ignition off. Turn ignition on again and let pump run for 5 seconds. Again, collect fuel in measuring container for 5 seconds. If amount of fuel collected is 3-5 ounces (94-157 cc), go to next step. If amount of fuel collected is less than 3 ounces (94 cc), clean fuel pump inlet screen and repeat this test. If fuel volume is still not within specifications, replace fuel pump and go to step  2).

  18. 24) Check Fuel Pump Valve Leakdown

    Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - VILLAGER article. Install fuel pressure gauge in fuel line between fuel filter and fuel rail. Turn ignition on. Fuel pump will run for 5 seconds. Monitor fuel pressure on fuel pressure gauge for 3 minutes. If fuel pressure drops more than 8 psi (55 kPa) in 3 minutes, replace fuel pump. Recheck fuel pressure and repeat QUICK TEST . If fuel pressure does not drop 8 psi (55 kPa) within 3 minutes, go to step  40).
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 24) to step 30). No test procedures have been omitted.

  19. 30) Check Fuel Pressure Regulator For Cause Of High Pressure

    Check for leaks in engine vacuum system due to loose or misthreaded fittings, cracks, or blockage that could cause insufficient vacuum to properly control fuel pressure regulator. Check fuel pressure regulator housing for damage or dents that could cause a higher spring load on fuel pressure regulator. Check integrity of fuel pressure regulator diaphragm in step  22). Replace fuel pressure regulator if necessary and go to step  2). If fuel pressure is still high, go to next step. If fuel pressure regulator is okay, go to next step.

  20. 31) Check Fuel Return For Cause Of High Fuel Pressure

    Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - VILLAGER article. Disconnect fuel return line at fuel pressure regulator and at fuel tank. Provide a suitable fuel receptacle at tank end of return line to avoid fuel spillage. Check fuel return line for restriction due to blockage, kinking, or pinching by blowing through fuel return line with 5-10 psi (35-69 kPa) of regulated shop air. If return line is restricted, repair or replace as necessary and go to step  2). If line is not restricted, replace fuel pressure regulator and go to step  2). If fuel pressure is still high, go to step  40).
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 31) to step 40). No test procedures have been omitted.

  21. 40) Check Fuel Injection Function

    With engine at normal operating temperature and idling (cranking if engine won't start), listen for a regular clicking sound from each injector using a stethoscope. If a regular clicking sound can be heard from each injector, go to step  43). If a regular clicking sound cannot be heard from each injector, go to next step.

  22. 41) Check Fuel Injector Resistance

    Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - VILLAGER article. Disconnect fuel injector harness connectors. Using DVOM, measure resistance of each fuel injector. If all resistances are 10-14 ohms, go to next step. If resistance is not 10-14 ohms, replace faulty injector(s) and repeat step  40). If testing in step 40)  shows components are okay, go to step  43).

  23. 42) Check Fuel Injector Electrical Signal

    Disconnect fuel injector. Insert fuel injector checker noid light into injector harness connector. Start or crank engine and observe noid light. Repeat procedure for all injectors. If all injector circuits indicate continuity, go to next step. If any injector circuit does not indicate continuity, check for 12 volts at each injector connector. Repair as necessary. Go to TEST H  , step  45) to diagnose fuel injector circuits.
    24. NOTE: The following procedure does not require matching of injector color with flow gauge band color.

  24. 43) Check Injectors For Leakage
    Turn ignition off. Release fuel system pressure. Remove fuel rail assembly from intake manifold (leave hoses and injectors attached). Turn ignition on (do not crank engine). If any injector leakage is observed, replace or clean leaky injector. Repeat QUICK TEST . If no injector leakage is observed, fuel delivery system is okay. Fault may be intermittent. Go to TEST Z  , step  1), or go to INTERMITTENTS in TROUBLE SHOOTING - NO CODES - VILLAGER article.
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