4: Verify The Customer Concern

Preliminary Inspection

4: Verify the Customer Concern

Verify the customer concern by carrying out a road test, and engine run-up test or both.

The decision to carry out a road test, an engine run-up test or both depends on the type of NVH (Noise, Vibration, or Harshness) symptom. A road test may be necessary if the symptom relates to the suspension system or is sensitive to torque. A DERU (Drive Engine Run-Up) or a NERU (Neutral Engine Run-Up) test identifies noises and vibrations relating to engine and drivetrain rpm. Remember, a condition will not always be identifiable by carrying out these tests, however, they will eliminate many possibilities if carried out correctly.