Diagnostic Test
- CHECK FOR RELATED TSBS AND DTCS NOTE:
If there are DTCs present in the PCM, TCM, or ABS Modules, repair the DTCs before proceeding.
- Check for any TSBs or, PCM or CCN software updates that may relate to customer's complaint.
- Follow the appropriate diagnostic procedure in the TSB.
Is vehicle repaired?
Yes
- Repair complete.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 2
- VISUAL INSPECTION
- Perform an inspection of the following:
- Verify there are no external fuel or coolant leaks.
- Verify the oil level. An excessively high or low oil level may cause a performance issue.
- Visually inspect the air filter for a restriction.
- Verify that the battery voltage is between 12.5 and 14.0 Volts when running.
- Verify that there are no Non-OEM engine modifications installed on the vehicle.
- Verify proper fuel level.
- Listen for any obvious intake or exhaust leaks.
- Verify that the accelerator pedal has full range of motion and monitor its function. Using the scan tool, go to the Data Tab and view Commanded Accelerator Position value. The value changes from 0-100% when actuated full travel.
Were there any problems found related to the above conditions?
Yes
- Repair as necessary and verify repair.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 3
- Perform an inspection of the following:
- CHECK PARASITIC LOSSES
- Check front end accessory driven components for proper function. In particular, look for excessive dragging on the front end accessory drive belt. Also, look for proper function of the A/C Compressor Clutch and Cooling Fan Clutch.
- Alternator.
- Power Steering Pump.
- Idler Pulley / Belt Tensioner.
- Water Pump.
- A/C Compressor.
- Cooling Fan Clutch.
- Check Drivetrain/Vehicle Operation.
- Verify brakes are not dragging.
- Verify vehicle is not stuck in four wheel drive mode, if equipped.
- Verify transmission and driveline are functioning properly.
- Verify tire size and style are not causing excessive resistance.
- Verify PTO is disengaging, if equipped.
Were any of the above components found to have an issue?
Yes
- Repair as necessary and verify repair.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 4
- Check front end accessory driven components for proper function. In particular, look for excessive dragging on the front end accessory drive belt. Also, look for proper function of the A/C Compressor Clutch and Cooling Fan Clutch.
- CHECKING FUEL QUALITY/CONTAMINATION
- Check the quality of the fuel using the DIESEL FUEL CONTAMINATION TEST PROCEDURE. Refer to DIESEL FUEL CONTAMINATION TESTING PROCEDURE
.
Was any contamination detected?
Yes
- Perform the appropriate repair according to the testing and cleaning procedure.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 5
- Check the quality of the fuel using the DIESEL FUEL CONTAMINATION TEST PROCEDURE. Refer to DIESEL FUEL CONTAMINATION TESTING PROCEDURE
.
- CHECK CRANKCASE FILTER
- Verify proper Crankcase Filter operation. Refer to DIAGNOSIS AND TESTING - CLOSED CRANKCASE VENTILATION (CCV)
.
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 6
- Verify proper Crankcase Filter operation. Refer to DIAGNOSIS AND TESTING - CLOSED CRANKCASE VENTILATION (CCV)
.
- PERFORM FUEL SYSTEM RUN-UP TEST
- Using the scan tool, perform the Fuel System Run Up test procedure.NOTE:
The PCM will cut out each individual Fuel Injector three times and calculate the delta RPM change. Based on the delta RPM change, the test will indicate a bad cylinder based on the limits that have been set. When the test is complete, the engine will return to idle. This test routine should also be used to validate that the system is operating properly after the repairs are completed.
NOTE:DTC P2201 will set while this test is running, and can be disregarded. After the test has finished, this code can be cleared and should not be diagnosed.
Do the results indicate that a cylinder is out of spec?
Yes
- Go To 7
No
- Go To 12
- Using the scan tool, perform the Fuel System Run Up test procedure.
- CHECKING FUEL INJECTOR AND VALVE COVER HARNESS TERMINALS
- Turn the ignition off.
- Visually inspect the integrated valve cover gasket injector harness connections for damaged wiring. Also inspect the nuts mounted to injector posts for loose connections or cross-threaded conditions that have damaged injector post threads.
- Check the torque of the Fuel injector nuts.NOTE:
The Fuel injector nuts should be torqued to 13.0 in/lbs.
Are the Fuel injector nuts torqued correctly and the connections and terminals good?
Yes
- Go To 8
No
- Repair the connections as necessary.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- CHECKING VALVE LASH
- Check the valve lash adjustment on the suspect cylinder or cylinders.
Is the valve lash within specification?
Yes
- Go To 9
No
- Adjust the valve lash to specifications.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- Check the valve lash adjustment on the suspect cylinder or cylinders.
- COMPRESSION CHECK
- Perform the Cylinder Compression Test. Refer to DIAGNOSIS AND TESTING
.
Is the compression within specification?
Yes
- Go To 11
No
- Go To 10
- Perform the Cylinder Compression Test. Refer to DIAGNOSIS AND TESTING
.
- CYLINDER LEAKAGE TEST
- Perform the Cylinder Leakage Test. Refer to DIAGNOSIS AND TESTING
.
Did the test show Cylinder Leakage within specs specification?
Yes
- Go To 11
No
- If it is determined that the low compression is caused a by piston or cylinder head/valve condition: Repair as necessary. Also, inspect and clean any soot fouling in the Air Handling and Exhaust systems as needed.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- Perform the Cylinder Leakage Test. Refer to DIAGNOSIS AND TESTING
.
- FUEL INJECTORS
- Change the Fuel Injector with a Fuel Injector from another good cylinder.
- With the scan tool, perform the Fuel System Run-up test.
Did the performance issue follow the Fuel Injector?
Yes
- Replace the Fuel Injector and check for fuel contamination. If fuel is found to be contaminated determine the point of entry of the contamination and repair. Inspect and clean any soot fouling in the Air Handling and Exhaust systems as needed.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 12
- CHECK THE FUEL DELIVERY SYSTEM
- Perform the CHECKING THE FUEL DELIVERY SYSTEM diagnostic procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM
.
Were any fuel system issues found?
Yes
- Repair the Fuel Delivery System. Inspect and clean any soot fouling in the Air Handling and Exhaust systems as needed.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 13
- Perform the CHECKING THE FUEL DELIVERY SYSTEM diagnostic procedure. Refer to CHECKING THE FUEL DELIVERY SYSTEM
.
- CHECK THE ENGINE PRESSURE SENSORS
- Turn the engine off, ignition on.
- With the scan tool, compare the Ambient Air Pressure Sensor reading and the Exhaust Manifold Pressure Sensor reading.
Are the two readings equal?
Yes
- Go To 14
No
- Compare the two readings to the Boost Pressure Sensor reading. Replace the sensor that does not match the Boost Pressure Sensor.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- CHECKING THE INTAKE SYSTEM
- Check for inlet restriction, inspect air filter for excessive dirt/debris. Verify air intake lines are not kinked or restricted.
- Using the scan tool, run the Ram Active Air Box test while observing the Intake Air Diverter Valve and the actuator rod (in the Air Cleaner).
- Refer to INTAKE AIR SYSTEM PRESSURE TEST and perform the CHECKING THE INTAKE AIR SYSTEM PRESSURE diagnostic procedure.
Were any problems found?
Yes
- Repair as necessary. Inspect and clean any soot fouling in the Air Handling and Exhaust systems as needed.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 15
- INSPECT TURBOCHARGER FOR WHEEL CLEARANCE
- Inspect Turbocharger Wheel Clearance. Refer to TURBOCHARGER, INSPECTION, 6.7L
.
Is the Turbocharger Wheel Clearance out of spec?
Yes
- Replace the Turbocharger assembly in accordance with the service information. Refer to TURBOCHARGER, REMOVAL, 6.7L .
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 16
- Inspect Turbocharger Wheel Clearance. Refer to TURBOCHARGER, INSPECTION, 6.7L
.
- INSPECT TURBOCHARGER FOR PROPER VGT OPERATION NOTE:
It is important to drain engine coolant before Electronic Turbo Actuator removal.
- Remove the Electronic Turbo Actuator from the Turbocharger.
- Inspect Electric Turbo Actuator for a broken/damaged drive gear.
Is the VGT actuator drive gear broken/damaged?
Yes
- Replace the Electronic Turbo Actuator in accordance with the service information. Refer to ACTUATOR, TURBOCHARGER, REMOVAL, 6.7L .
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 17
- TURBOCHARGER
- Inspect the sector gear on the Turbocharger for damage or broken teeth.
- Move the sector gear lever on the turbocharger bearing housing up and down from mark to mark.
- Check for smooth movement between the sector gear marks on the turbo bearing housing.NOTE:
There will be an initial friction force that must be overcome before the actuator lever will move. Once movement is started, the actuator lever must move to the other marked position by hand.
Does the nozzle slide evenly from stop to stop and are the gear teeth undamaged?
Yes
- Replace the Electronic Turbo Actuator in accordance with the Service Information. Refer to ACTUATOR, TURBOCHARGER, REMOVAL, 6.7L .
- Then, Go To 18
No
- Replace the Turbocharger assembly in accordance with the Service Information. Refer to TURBOCHARGER, REMOVAL, 6.7L .
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- CHECKING THE EGR AIRFLOW CONTROL VALVE OPERATION
- With the ignition off, remove the inlet hose to the EGR Airflow Control Valve.
- Use a mirror to inspect the valve while an assistant cycles the ignition on and off several times.
Does the EGR Airflow Control Valve cycle open and close without sticking when the ignition is cycled on and off?
Yes
- If the soot inside the EGR Crossover Tube is oily, inspect the Turbocharger for leaking oil into the intake system. If Turbo is leaking, replace the Turbo. If Turbo is not leaking, clean the Crossover Tube, remove and clean the EGR Valve and EGR Cooler.
- Go To 19
No
- Check the electrical circuits for the EGR Airflow Control Valve. If the wiring is good, replace the EGR Airflow Control Valve.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- CHECKING THE EGR SYSTEM
- Perform the following EGR system checks:
- Look for visible signs (soot streaks) of an external EGR system leak.
- Remove the EGR Temperature Sensor and check for blockage or debris.
- Remove EGR Crossover Tube from EGR Cooler and EGR Valve. Inspect the tube for a restriction.
- Verify EGR Cooler is not leaking. Check for coolant in EGR plumbing, engine overheat fault codes, and low coolant level.
- Check the Air Intake Grid Heater for excessive soot build up or restriction.
Were any problems found?
Yes
- If the soot inside the EGR Crossover Tube is oily, inspect the Turbocharger, Exhaust Manifold and exhaust ports for oil leaking into the intake system. If oil is leaking from engine, check valve stem seals and power cylinder components. If the Turbocharger is leaking oil into intake system, replace the Turbocharger. If Turbocharger is not leaking, clean the Crossover Tube, remove and clean the EGR Valve and EGR Cooler.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 20
- Perform the following EGR system checks:
- CHECK THE EXHAUST SYSTEM FOR LEAKS
- Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS
.
Were any exhaust leaks found?
Yes
- Perform the appropriate repair.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 21
- Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS
.
- CHECK THE EXHAUST AFTERTREATMENT SYSTEM FOR A RESTRICTION
- Perform the AFTERTREATMENT INSPECTION GUIDELINE procedure. Refer to AFTERTREATMENT INSPECTION GUIDELINE
.
Were any problems found during inspection?
Yes
- Perform the appropriate repair.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Perform the DIESEL FUEL VALIDATION procedure. Refer to STANDARD PROCEDURE . If the vehicles passes the validation, the vehicle is operating properly. If the vehicle fails the validation, the issue was missed during Diagnostics.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- Perform the AFTERTREATMENT INSPECTION GUIDELINE procedure. Refer to AFTERTREATMENT INSPECTION GUIDELINE
.