Diagnostic Test
- ACTIVE DTC NOTE:
This fault can potentially be set by an aftermarket Air Filter Box and/or filter. Non factory filter assemblies are not calibrated to the factory PCM thresholds or settings. If the vehicle has a modified filter assembly and this fault is set, notify the customer that the vehicle needs to be returned back to the stock assembly in order to properly repair the vehicle.
NOTE:If there are any other EGR, Turbocharger, or Intake system DTCs present, repair those DTCs before proceeding.
- Turn the ignition on.
- With the scan tool, record all Freeze frame data.
- With the scan tool, erase DTCs.
- Turn the ignition off for 75 seconds.
- Start the engine attempt to duplicate the conditions that set the DTC.
- With the scan tool, read DTCs.
Did the DTC return?
Yes
- Go To 2.
No
- Perform the INTERMITTENT CONDITION - 6/7L diagnostic procedure. Refer to INTERMITTENT CONDITION - 6.7L .
- CHECK THE MAF SENSOR
- Start the engine. Warm the engine up to operating temperature and then let it idle for five minutes.NOTE:
This is how long it takes for the EGR Valve to close.
- With the scan tool in Data Display, verify that the EGR Valve is at 0%.
- With the scan tool, read the MAF Sensor value.
Does the Mass Air Flow Sensor read from 1.36 - 3.07 kg/min for an auto transmission, or 1.58 - 3.41 kg/min for a manual transmission?
Yes
- Go To 3.
No
- Replace the Mass Air Flow Sensor in accordance with the service information.
- Perform the POWERTRAIN VERIFICATION TEST TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
- Start the engine. Warm the engine up to operating temperature and then let it idle for five minutes.
- CHECK THE AIR FILTER
- Remove lid from air filter box.
- Remove air filter and inspect for excessive debris or filter media damage.
- Make sure the filter was installed properly.
Is the air filter damaged or full of debris (restricted)?
Yes
- Replace the Air Filter.
- Perform the POWERTRAIN VERIFICATION TEST TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
No
- Go To 4.
- CHECK THE MAF SENSOR
- Turn the Ignition off.
- Remove MAF sensor from the air filter box.
Is it free from debris?
Yes
- Go To 5.
No
- Clean the Mass Air Flow Sensor using low pressure air and reinstall, repair complete.
- Perform the POWERTRAIN VERIFICATION TEST TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
- CHECK FOR AN AIR LEAK IN THE INTAKE SYSTEM
- Perform the INTAKE AIR SYSTEM PRESSURE TEST diagnostic procedure. Refer to Diagnosis and Testing , 6.7L .
- Any leak between the air box to the intake manifold could cause this fault.
Were there any Intake Air System leaks?
Yes
- Repair the leak in the Intake Air System.
- Perform the POWERTRAIN VERIFICATION TEST TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
No
- Replace the Mass Air Flow Sensor in accordance with the service information.
- Perform the POWERTRAIN VERIFICATION TEST TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .