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).

Refer to the Engine Mechanical and the Engine Performance diagnostic charts, for possible causes and corrections of malfunctions. See DIAGNOSIS AND TESTING .

For fuel system diagnosis, refer to FUEL SYSTEM article.

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

1. CYLINDER COMPRESSION PRESSURE TEST 
2. CYLINDER COMBUSTION PRESSURE LEAKAGE TEST 
3. CYLINDER HEAD GASKET  Failure Diagnosis
4. INTAKE MANIFOLD LEAKS 
5. HYDRAULIC LIFTERS  Adjuster Noise Diagnosis
6. ENGINE OIL LEAK INSPECTION