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Symptom Chart

SYMPTOM CHART

Condition Possible Sources Action
  • Difficult starting
  • Damaged ignition system.
  • REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Damaged fuel system.
  • Refer to FUEL SYSTEM for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Damaged starting system.
  • Refer to STARTERS for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Damaged charging system/battery.
  • Burnt valve.
  • INSTALL a new valve.
  • Worn piston.
  • INSTALL a new piston.
  • Worn piston rings.
  • INSTALL new piston rings.
  • Worn cylinder.
  • REPAIR or INSTALL a new cylinder block.
  • Damaged head gasket.
  • INSTALL a new head gasket.
  • Damaged cooling system.
  • Refer to ENGINE COOLING for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Poor idling
  • Vacuum leaks.
  • for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Malfunctioning or damaged ignition system.
  • REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Malfunctioning or damaged fuel system.
  • Refer to FUEL SYSTEM for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Damaged valve tappet or lash adjuster.
  • INSTALL a new valve tappet or lash adjuster.
  • Damaged valve tappet guide or lash adjuster.
  • INSTALL a new valve tappet guide or valve tappet.
  • Incorrect valve-to-valve seat contact.
  • REPAIR or INSTALL a new valve or valve seat.
  • Damaged head gasket.
  • INSTALL a new head gasket.
  • Abnormal combustion
  • Malfunctioning or damaged fuel system.
  • Refer to FUEL SYSTEM for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Malfunctioning or damaged ignition system.
  • REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Malfunctioning or damaged air intake system.
  • Refer to INTAKE AIR for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Damaged valve tappet or lash adjuster.
  • INSTALL a new valve tappet or lash adjuster.
  • Damaged valve tappet guide or valve tappet.
  • INSTALL a new valve tappet guide or valve tappet.
  • Burnt or sticking valve.
  • REPAIR or INSTALL a new valve.
  • Weak or broken valve spring.
  • INSTALL a new valve spring.
  • Carbon accumulation in combustion chamber.
  • ELIMINATE carbon buildup.
  • Excessive oil consumption
  • Leaking oil.
  • REPAIR oil leakage.
  • Malfunctioning PCV system.
  • REPAIR or INSTALL new necessary components.
  • Worn valve stem seal.
  • INSTALL a new valve stem seal.
  • Worn valve stem or valve guide.
  • INSTALL a new valve and valve guide.
  • Sticking piston rings.
  • REPAIR or INSTALL new piston rings.
  • Worn piston ring groove.
  • INSTALL a new piston and piston pin.
  • Worn piston or cylinder.
  • REPAIR or INSTALL a new piston or cylinder block.
  • Engine noise
  • Leaking exhaust system.
  • REPAIR exhaust leakage.
  • Incorrect drive belt tension.
  • Malfunctioning generator bearing.
  • Malfunctioning water pump bearing.
  • Malfunctioning or damaged cooling system.
  • Malfunctioning or damaged fuel system.
  • Refer to FUEL SYSTEM for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Loose timing chain/belt (6268).
  • ADJUST or INSTALL a new timing chain/belt.
  • Damaged timing chain tensioner (6L266).
  • INSTALL a new timing chain tensioner.
  • Excessive main bearing clearance.
    CAUTION: Remove the cylinder heads before removing the crankshaft. Failure to do so can result in engine damage.
  • ADJUST clearance or INSTALL a new crankshaft main bearing (6333).
  • Seized or heat-damaged crankshaft main bearing.
  • INSTALL a new crankshaft main bearing.
  • Excessive crankshaft end play.
  • INSTALL a new thrust bearing or crankshaft (6303).
  • Excessive connecting rod bearing clearance.
  • INSTALL a new connecting rod bearing or connecting rod (6200).
  • Heat damaged connecting rod bearing (6211).
  • INSTALL a new connecting rod bearing.
  • Damaged connecting rod bushing (6207).
  • INSTALL a new connecting rod bushing.
  • Worn cylinder.
  • REPAIR or INSTALL a new cylinder block (6010).
  • Worn piston (6108) or piston pin (6135).
  • INSTALL a new piston or piston pin.
  • Damaged piston rings.
  • INSTALL new piston rings.
  • Bent connecting rod.
  • INSTALL a new connecting rod.
  • Malfunctioning valve tappet (6500) or lash adjuster.
  • INSTALL a new valve tappet or lash adjuster.
  • Excessive valve tappet or lash adjuster clearance.
  • ADJUST clearance or INSTALL a new valve tappet guide or valve tappet.
  • Broken valve spring (6513).
  • INSTALL a new valve spring.
  • Excessive valve guide clearance.
  • ADJUST clearance or INSTALL a new valve guide (6510) or valve.
  • Insufficient power
  • Malfunctioning or damaged ignition system.
  • REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Malfunctioning or damaged fuel system.
  • Refer to FUEL SYSTEM for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  1. Malfunctioning or damaged air intake system.
  • Refer to INTAKE AIR for the procedure. REFER to the INTRODUCTION article in ENGINE PERFORMANCE.
  • Damaged or plugged exhaust system.
  • INSPECT exhaust system.
  • Incorrect tire size.
  • Dragging brakes.
  • Slipping transmission.
  • Malfunctioning valve tappet or lash adjuster.
  1. INSTALL a new valve tappet or lash adjuster.
  • Damaged valve tappet guide or valve tappet.
  • INSTALL a new valve tappet guide or valve tappet.
  • Compression leakage at valve seat.
  • REPAIR or INSTALL a new valve, valve seat or cylinder head (6049).
  • Seized valve stem.
  • INSTALL a new valve.
  • Weak or broken valve spring.
  • INSTALL a new valve spring.
  • Worn or damaged camshaft.
  • INSTALL a new camshaft.
  • Damaged head gasket (6051).
  1. INSTALL a new head gasket.
  • Cracked or distorted cylinder head.
  • INSTALL a new cylinder head.
  • Damaged, worn or sticking piston ring(s).
  • REPAIR or INSTALL a new piston ring(s).
  • Worn or damaged piston.
  • INSTALL a new piston and piston pin.
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