Perform the Diagnostic System Check - Vehicle.

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 condition. The diagnostic flow is the place to start when repairs are necessary.

• Inspect for aftermarket devices which could affect the operation of the engine.
• Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
• Inspect 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.

Test the vehicle under the same conditions that the customer reported in order to verify the system is operating properly.

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

• Engine Noise Under Load
• Base Engine Misfire without Internal Engine Noises
• Base Engine Misfire with Abnormal Internal Lower Engine Noises
• Base Engine Misfire with Abnormal Valve Train Noise
• Base Engine Misfire with Coolant Consumption
• Base Engine Misfire with Excessive Oil Consumption
• Engine Noise on Start-Up, but Only Lasting a Few Seconds
• Upper Engine Noise, Regardless of Engine Speed
• Lower Engine Noise, Regardless of Engine Speed
• Engine Will Not Crank - Crankshaft Will Not Rotate
• Coolant in Engine Oil
• Engine Compression Test
• Oil Consumption Diagnosis
• Oil Pressure Diagnosis and Testing
• Oil Leak Diagnosis
• Drive Belt Chirping, Squeal, and Whine Diagnosis
• Drive Belt Rumbling and Vibration Diagnosis
• Drive Belt Falls Off and Excessive Wear Diagnosis
• Drive Belt Tensioner Diagnosis