FixVault
Home › Ford › 2011 › Expedition RWD › Repair and Diagnosis › Engine Mechanical › Mechanical › Engine System - General Information › Description And Testing › Engine › Inspection and Verification - Engine NVH › Notes

Inspection and Verification - Engine NVH: Notes

  1. Engine NVH symptoms should be identified using the diagnostic tools and techniques that are available. For a list of these techniques, tools, an explanation of their uses and a glossary of common terms, refer to NOISE, VIBRATION & HARSHNESS .
  2. Verify the customer concern by operating the engine to duplicate the condition.
  3. Inspect the engine for installation of an aftermarket oil filter. Review oil and filter maintenance history to make sure that the vehicle has not gone beyond the standard Ford recommended oil change interval.
  4. Check the engine oil level and check the oil for contamination. Low engine oil level or contaminated oil are common causes of engine noise. If the oil is contaminated the source of the contamination must be identified and repaired as necessary.
  5. Visually inspect for obvious signs of mechanical damage. Refer to the following chart.
    VISUAL INSPECTION CHART

    Mechanical
    • Loose mounting bolts, studs and nuts
    • Damaged or leaking powertrain mounts
    • Damaged or disconnected vacuum hoses
    • Damaged or disconnected air intake components
    • Obstruction of cooling fan
    • Obstruction of Front End Accessory Drive (FEAD)
    • Obstruction of Rear End Accessory Drive (READ), if equipped
  6. If the inspection reveals obvious concerns that can be readily identified, repair as necessary.
    7. NOTE: Make sure to use the latest scan tool software release.
  7. If the cause is not visually evident, connect the scan tool to the DLC  .
    8. NOTE: The VCM  LED prove out confirms power and ground from the DLC  are provided to the VCM  .
  8. If the scan tool does not communicate with the VCM  :
    • check the VCM  connection to the vehicle.
    • check the scan tool connection to the VCM  .
    • Refer to MODULE COMMUNICATIONS NETWORK , No Power To The Scan Tool, to diagnose no power to the scan tool.
  9. If the scan tool does not communicate with the vehicle:
    • verify the ignition key is in the ON position.
    • verify the scan tool operation with a known good vehicle.
    • Refer to MODULE COMMUNICATIONS NETWORK to diagnose no response from the PCM.
  10. Carry out the network test.
    • If the scan tool responds with no communication for one or more modules, refer to MODULE COMMUNICATIONS NETWORK .
    • If the network test passes, retrieve and record Continuous Memory Diagnostic Trouble Codes (CMDTCs).
  11. Clear the continuous DTCs and carry out the self-test diagnostics for the PCM.
  12. If the DTCs retrieved are related to the concern, refer to MULTIFUNCTION ELECTRONIC MODULE .
  13. If no DTCs related to the concern are retrieved, continue the inspection and verification if a noise concern is related to the engine. For vibration concerns and noise concerns such as powertrain mounts, air intake system and starter, go to SYMPTOM CHART - ENGINE NVH .

In some cases, a noise may be a normal characteristic of that engine type. In other cases, the noise may require further investigation. Comparing the noise to a similar year/model vehicle equipped with the same engine will aid in determining if the noise is normal or abnormal.

Once a customer concern has been identified as an abnormal engine noise, it is critical to determine the location of the specific noise. Use the EngineEAR/ChassisEAR or stethoscope (the noise will always be louder the closer you get to the noise source) to isolate the location of the noise to one of the following areas.

About FixVault