Strategy Based Diagnostics
- Perform
Diagnostic System Check - Engine Controls in Engine Controls before
using the symptom tables (if applicable).
- Review the system operations in order to familiarize yourself
with the system functions. Refer to
Disassembled Views,
Engine Component Description,
Lubrication Description, and
New Product Information
in Engine Unit Repair Manual and to
Drive Belt System Description.
All diagnosis on a vehicle should follow a logical process. Strategy
based diagnostics is a uniform approach for repairing all systems. The diagnostic
flow may always be used in order to resolve a system problem. The diagnostic
flow is the place to start when repairs are necessary. For a detailed explanation,
refer to Strategy Based Diagnosis in General Information.
Visual/Physical Inspection
| • | Inspect for aftermarket devices which could affect the operation
of the Engine. Refer to Aftermarket Accessories in Wiring Systems. |
| • | Inspect the easily accessible or visible system components for
obvious damage or conditions which could cause the symptom. |
| • | Check for the correct oil level, proper oil viscosity, and correct
filter application. |
| • | Verify the exact operating conditions under which the concern
exists. Note factors such as engine RPM, ambient temperature, engine temperature,
amount of engine warm-up time, and other specifics. |
| • | Compare the engine sounds (if applicable) to a known good engine
and make sure you are not trying to correct a normal condition. |
Intermittent
Test the vehicle under the same conditions that the customer reported
in order to verify the system is operating properly.
Symptom List
Refer to a symptom diagnostic procedure from the following list in order
to diagnose the symptom:
