Diagnosis And Testing: 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 mechanical (e.g., a strange noise), or performance (e.g., engine idles rough and stalls).

For Engine Mechanical diagnosis, refer to MECHANICAL  .

For Engine Performance diagnosis, refer to PERFORMANCE  .

For Fuel Delivery system diagnosis, refer to FUEL SYSTEM .

For cooling system diagnosis, refer to COOLING SYSTEM, DIAGNOSIS AND TESTING .

For Engine Lubrication System diagnosis, refer to LUBRICATION, DIAGNOSIS AND TESTING  .

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

• Cylinder Compression Pressure Test: Refer to CYLINDER COMPRESSION PRESSURE TEST .
• Cylinder Combustion Pressure Leakage Test: Refer to CYLINDER COMBUSTION PRESSURE LEAKAGE TEST .
• Cylinder Head Gasket Leakage Diagnosis: Refer to DIAGNOSIS AND TESTING - CYLINDER HEAD GASKET .
• Intake Manifold Leakage Diagnosis: Refer to DIAGNOSIS AND TESTING - INTAKE MANIFOLD LEAKS .
• Mechanical Valve Tappet Noise Diagnosis: Refer to DIAGNOSIS AND TESTING - MECHANICAL VALVE TAPPET NOISE DIAGNOSIS .
• Exhaust System leak testing: Refer to EXHAUST SYSTEM DIAGNOSIS .
• Engine Oil Leak Inspection: Refer to ENGINE OIL LEAK INSPECTION .