Title: Diagnose abnormal engine noises or vibration concerns; determine the needed action.
Course: Automotive Technology III (20104-III) > Section: ENGINE PERFORMANCE: General-Engine Diagnosis

Diagnosis should include

- searching for loose components
- checking for misalignment of components
- listening unaided or with a stethoscope or other sound detector to locate the source of noise
- locating vibrations caused by a misfire or by worn/faulty components
- using a scan tool to isolate misfires.

Process/Skill Questions:

- What tool would the technician use to pinpoint the source of a noise?
- How can engine mount vibrations be tested?
- What would a low, knocking noise indicate?
- What are the differences between high- and low-speed noise/vibrations?