Section D - Engine Will Not Start / Hard to Start

Perform the Pre-Diagnostic Troubleshooting Procedure before proceeding.

1. DTC / Product Improvement: Check for any service bulletins related to the customer's concern or Diagnostic Trouble Codes (DTC's) present. Follow appropriate guidelines in the diagnostic procedures outlined in TechCONNECT. Is the vehicle repaired?

a. Yes >> Go to Step # 17.

b. No >> Go to Step # 2.

2. Verify Battery Voltage: Measure the battery voltage and load capability. Is the battery voltage sufficient?

a. Yes >> Go to Step # 3.

b. No >> Repair low battery voltage condition. Go to Step # 17.

3. Verify Starting Accessories: Verify the ignition switch, vehicle theft system, starter, intake manifold grid heater, and fuel heater are functioning properly. Are all starting accessories functioning properly?

a. Yes >> Go to Step # 4.

b. No >> Repair or replace accessories as necessary >> Go to Step # 17.

4. Check the supply fuel in the vehicle: Verify fuel level in the fuel tank. Also verify fuel quality. Remove, inspect and replace the fuel filter (if necessary). Investigate for evidence of fuel contamination and improper fuel type. Refer to the vehicle owners manual fuel requirements section. Is the fuel quality within specification?

a. Yes >> Go to Step # 5.

b. No >> Follow fuel contamination process (drain contaminated fuel, replace damaged components, fill with proper fuel). >> Go to Step # 17.

5. Verify complaint: Using the appropriate scan tool log the fuel pressure set point and actual fuel pressure. Verify the rail pressure versus set point, this can be done while cranking or with the engine idling. A good system will have actual fuel pressure that is +/- 500 PSI from the set pressure. (Example: If the fuel pressure set point at idle is 6500 PSI, the actual fuel pressure on a good system is expected to be between 6000 - 7000 PSI). Does the actual fuel rail pressure meet the set fuel pressure +/- 500 PSI?

a. Yes >> Go to Step # 6.

b. No >> Go to Step # 9.

6. Check the engine oil level: Check the engine oil level. Is the engine oil level over filled?

a. Yes >> Go to Step # 7.

b. No >> Go to Step # 8.

7. Remove the engine valve cover: Inspect for injectors leaking fuel into the valve train area while cranking the engine. If the engine will start and idle, actuate the Fuel Pressure Override Test on the appropriate scan tool NOTE: This feature is not available on 2003 MY vehicles. Use the fuel manifold blocking tool, Miller special tool # 9011, to isolate suspected leaking injectors. If the leak is still present with the suspected injector isolated, remove the injector and inspect the 0-ring on the body of the injector for cuts or damage. Inspect the injector bore for burrs or other cause for a cut 0-ring. Correct the cause of the damaged 0-ring and replace the 0-ring. Use copper sealing gasket when reinstalling the injector. Refer to the detailed removal and installation procedures available in TechCONNECT under: Service Info tab > 14 - Fuel System > Fuel Injection > Fuel Injector. Are there any leaking injectors?

a. Yes >> Replace the leaky injector(s). Refer to the detailed removal and installation procedures available in TechCONNECT under: Service Info tab > 14 - Fuel System > Fuel Injection > Fuel Injector. >> Go to Step # 17.

b. No >> Determine the source of fuel/coolant/other substance in the crankcase causing the system to be over full. Repair as necessary. >> Go to Step # 17.

8. Check the fuel pressure limiting valve: Perform the "Checking Pressure Limiting Valve On The Fuel Rail For Internal Leaks" test. Perform the existing diagnostic procedure available in TechCONNECT under: Service Info tab > 9 - Engine > Diagnosis and Testing. No leakage is expected while cranking or while at idle speed.
Does the pressure limiting valve leak internally?

a. Yes >> Replace the fuel pressure limiting valve. - Refer to the detailed service information available in TechCONNECT under: Service Info tab > 14 - Fuel System > Fuel Delivery> Fuel Pressure Regulator. >> Go to Step # 17.

b. No >> Go to Step # 9.

9. Test for high injector return flow: Refer to the detailed diagnostic information available in TechCONNECT under: Service Info tab > 9 - Engine, Diagnosis and Testing > Injector Return Flow Test. Do the injectors pass the "Injector Return Flow Test"?

a. Yes >> Go to Step # 11.

b. No >> Go to Step # 10.

NOTE:
Torque all High Pressure Connector (HPC) nuts to the correct torque and retest. Refer to the detailed service information available in TechCONNECT under: Service Info tab > 14 - Fuel System> Fuel Injection > Fuel Injector.

NOTE:
Test should be repeated to confirm measurements.

10. If the injector return from any cylinder(s) is deemed excessive:

a. Check HPC tip for damage, replace HPC if damaged. Refer to the detailed service information available in TechCONNECT under: Service Info tab> 14 - Fuel System > Fuel Injection > Fuel Injector Removal/Installation. >> Go to Step # 17.

b. If HPC tip is undamaged, replace the injector and HPC. Refer to the detailed service information available in TechCONNECT under: Service Info tab > 14 - Fuel System > Fuel Injection > Fuel Injector > Removal/Installation. >> Verify that a quality fuel filter is used.� Go to Step # 17.

11. Verify proper low pressure fuel supply to the high pressure pump: Perform the appropriate fuel supply system flow test. NOTE: This procedure can be slightly different depending on if the vehicle has an engine-mounted transfer pump or the in-tank transfer pump. In a good low pressure fuel system, fuel flow of 560 mL in 10 seconds or better is expected for model year 2003 and early 2004 vehicles. In a good low pressure fuel system, fuel flow of 590 mL in 10 seconds or better is expected for model year late 2004 through 2007 vehicles. Be sure there is no air in the system.

Is the low pressure fuel supply volume sufficient?

a. Yes >> Go to Step # 12.

b. No >> Repair the low pressure fuel supply system. Vehicles equipped with an in tank fuel pump: Refer to the detailed diagnostic information available in TechCONNECT under: Service Info tab > 9 - Engine > Diagnosis & Testing > In-Tank Fuel Lift Pump Flow/Diagnostic Test Procedure. Vehicles equipped with an engine mounted fuel transfer pump: Refer to the detailed diagnostic information available in TechCONNECT under: Service Info tab > Diagnostics tab, Powertrain Gas, Driveability Diesel, Fuel Lift Pump Flow And Inlet Restriction Test � Go to Step # 17.

12. Verify high pressure pump output volume: Remove the high pressure fuel line from the high pressure pump outlet port to the fuel rail. Connect a suitable hose to the high pressure outlet port of the high pressure pump and route it to a graduated container. Disconnect the Electronic Fuel Control Actuator. Crank the engine until fuel exits the hose. NOTE: With the discharge line routed to atmosphere, fuel will discharge at 0 PSI. Crank the engine for three 10 second intervals, pausing to allow the starter to cool between each crank event. High pressure pump output volume must be greater than 70 mL in 30 seconds. Is the high pressure pump output flow sufficient?

a. Yes >> Go to Step # 13.

b. No >> Replace the high pressure pump. Refer to the detailed service information available in TechCONNECT under: Service Info tab > 14 - Fuel System > Fuel Injection > Fuel Injection Pump. � Go to Step # 17.

13. Fuel Return: Check for kinked or restricted fuel return lines. Check the fuel tank venting. Where any problems found in the Fuel Return system?

a. Yes >> Repair as necessary. >> Go to Step # 17.

b. No >> Go to Step #14.

14. Intake/Exhaust Systems: Check for inlet restriction, inspect air filter for excessive dirt/debris. Verify air intake tubes and hoses are not kinked or restricted. Check for charge air cooler air system leaks. Perform the "INTAKE AIR SYSTEM PRESSURE TEST - DIESEL". Refer to the detailed service information available in TechCONNECT under: Service Info tab > 11 - Exhaust System > Turbocharger System > Turbocharger > Inspection. Inspect the Turbocharger for excessive compressor wheel movement and proper waste gate operation. Check for exhaust restriction. Check for kin ked or blocked exhaust pipes. Verify proper exhaust brake operation (if equipped). Were any issues found with the Intake/Exhaust Systems?

a. Yes >> Repair as necessary. >> Go to Step # 17.

b. No >> Go to Step # 15.

15. Other Vehicle Systems: Verify proper operation of the Transmission Clutch. Verify proper operation of the Transmission. Verify proper operation of the Vehicle brakes (check for dragging). Verify proper operation of the Cooling fan operation cycle time. Verify proper operation of the Engine driven accessories. Were any issues found with the Other Vehicle Systems?

a. Yes >> Repair as necessary. >> Go to Step # 17.

b. No >> Go to Step # 16.

16. Base Engine: Check for internal engine damage. Valve lash settings, engine compression, cylinder leak down, etc. Were any issues found with the Base Engine?

a. Yes >> Repair as necessary. >> Go to Step # 17.

b. No >> Go to Step # 17.

17. Repair Complete: Perform Powertrain Verification Test VER - 1 (Diesel). Refer to the detailed service information available in TechCONNECT under: Service Info tab > 8 - Electrical/Electronic Control Modules/Engine Control Module > Diagnosis And Testing.