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Engine Mechanical

  1. Check engine mechanical for the following conditions:
    • Check the compression. See MECHANICAL INSPECTION in BASIC DIAGNOSTIC PROCEDURES - 3.1L CENTURY, GRAND PRIX & MALIBU article.
    • Sticking or leaking valves.
    • Worn camshaft lobes.
    • Worn camshaft lobes.
    • Valve timing.
    • Bent push rods.
    • Worn rocker arms.
    • Broken valve springs.
    • Excessive oil in combustion chamber. Leaking valve seals.
    • Low cylinder compression.
  2. Check for incorrect engine parts, such as the camshaft, cylinder heads, pistons, etc.
  3. Diagnose mechanical condition of the engine. See appropriate article in ENGINES.