Diagnosis And Testing-Engine Diagnosis-Introduction

Engine diagnosis is helpful in determining the causes of malfunctions not detected and remedied by routine maintenance.

These malfunctions may be classified as either performance (e.g., engine idles rough and stalls) or mechanical (e.g., a strange noise).

Refer to DIAGNOSIS AND TESTING-ENGINE DIAGNOSIS-PERFORMANCE  and (Refer to DIAGNOSIS AND TESTING-ENGINE DIAGNOSIS-MECHANICAL  for possible causes and corrections of malfunctions. Refer to FUEL SYSTEMS for the fuel system diagnosis.

Additional tests and diagnostic procedures may be necessary for specific engine malfunctions that can not be isolated with the Service Diagnosis charts. Information concerning additional tests and diagnosis is provided within the following diagnosis:

• Cylinder Compression Pressure Test (Refer to ENGINE-DIAGNOSIS AND TESTING ).
• Cylinder Combustion Pressure Leakage Test (Refer to ENGINE-DIAGNOSIS AND TESTING ).
• Intake Manifold Leakage Diagnosis (Refer to ENGINE/MANIFOLDS/INTAKE MANIFOLD-DIAGNOSIS AND TESTING ).