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Symptom Chart - Engine Performance

SYMPTOM CHART - ENGINE PERFORMANCE

Condition Possible Sources Action
  • Difficult starting
  • Inoperative or damaged ignition system
  • Air or vacuum leak
  • Inoperative or damaged fuel system
  • Inoperative or damaged starting system
  • Damaged charging system/battery
  • Burnt valve
  • INSTALL a new valve in the cylinder head. TEST the system for normal operation after the repair.
  • Worn piston
  • INSTALL a new piston. TEST the system for normal operation after the repair.
  • Worn piston rings
  • INSTALL new piston rings. TEST the system for normal operation after the repair.
  • Worn cylinder
  • INSTALL a new cylinder block. TEST the system for normal operation after the repair.
  • Damaged head gasket
  • INSTALL a new cylinder head gasket. TEST the system for normal operation after the repair.
  • Inoperative or damaged cooling system
  • Fail-safe cooling invoked (if equipped)
  • Poor idling
  • Vacuum leaks
  • Inoperative or damaged ignition system
  • Inoperative or damaged cooling system
  • Inoperative or damaged fuel system
  • Fail-safe cooling invoked (if equipped)
  • Incorrect valve clearance
  • Incorrect valve-to-valve seat contact
  • INSTALL a new cylinder head. TEST the system for normal operation after the repair.
  • Damaged head gasket
  • INSTALL a new cylinder head gasket. TEST the system for normal operation after the repair.
  • Engine runs rough
  • Inoperative or damaged fuel system
  • Air or vacuum leaks
  • Inoperative or damaged cooling system
  • Inoperative or damaged ignition system
  • Fail-safe cooling invoked (if equipped)
  • Burnt or sticking valve
  • INSTALL a new valve in the cylinder head. TEST the system for normal operation after the repair.
  • Weak or broken valve spring
  • INSTALL a new valve spring. TEST the system for normal operation after the repair.
  • Carbon accumulation in combustion chamber
  • ELIMINATE carbon buildup. TEST the system for normal operation after the repair.
  • Excessive oil consumption
  • Leaking oil
  • REPAIR oil leakage. TEST the system for normal operation after the repair.
  • Blocked or restricted turbocharger oil drain pipes
  • INSPECT the turbocharger oil drain pipes. REPAIR as necessary. TEST the system for normal operation after the repair.
  • Damaged or collapsed air intake hoses and tubes
  • TIGHTEN hose clamps. INSPECT for damage and REPAIR as necessary. TEST the system for normal operation after the repair.
  • Damaged exhaust or exhaust leaks at turbocharger housing or exhaust manifolds
  • INSPECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaping hot exhaust gases. REPAIR as necessary. TEST the system for normal operation after the repair.
  • Turbocharger oil seals leaking
  • Inoperative PCV system
  • REPAIR or INSTALL new components as necessary. TEST the system for normal operation after the repair.
  • Incorrect oil
  • CHANGE oil to correct specification.
  • Worn valve stem seal
  • INSTALL a new valve stem seal. TEST the system for normal operation after the repair.
  • Worn valve stem or valve guide
  • INSTALL a new cylinder head. TEST the system for normal operation after the repair.
  • Sticking piston rings
  • INSTALL new piston rings. TEST the system for normal operation after the repair.
  • Worn piston ring groove
  • INSTALL a new piston and piston pin. TEST the system for normal operation after the repair.
  • Worn piston or cylinder
  • INSTALL a new piston or cylinder block. TEST the system for normal operation after the repair.
  • Oil in coolant
  • Leaking head gasket
  • Damaged cylinder block
  • Damaged cylinder head
  • Coolant in oil
  • Leaking head gasket
  • Damaged cylinder block
  • Damaged cylinder head
  • Damaged coolant pump/seal/gasket
  • Insufficient power
  • Inoperative or damaged ignition system
  • Air intake system blockage
  • Lubrication system blockage
  • Inoperative or damaged fuel system
  • Turbocharger turbine or compressor wheel damage
  • Damaged exhaust or exhaust leaks at turbocharger housing or exhaust manifolds
  • INSECT for leaks. Leaks can usually be detected audibly or visually, by a discoloration caused by escaped hot exhaust gases. REPAIR as necessary. TEST the system for normal operation after the repair.
  • Malfunctioning turbocharger bypass valve
  • Oil level too high
  • DRAIN oil to correct level. TEST the system for normal operation after the repair.
  • Incorrect engine oil
  • INSTALL correct specification engine oil. TEST the system for normal operation after the repair.
  • Excessive accessory drive belt loading
  • Inoperative or damaged cooling system
  • Fail-safe cooling invoked (if equipped)
  • Damaged or plugged exhaust system
  • INSPECT exhaust system.
  • Incorrect tire size
  • Dragging brakes
  • Slipping transmission
  • Incorrect valve clearance
  • Worn or damaged valve tappet
  • INSTALL a new valve tappet. TEST the system for normal operation after the repair.
  • Damaged valve guide
  • Compression leakage at valve seat
  • Seized valve stem
  • INSTALL a new cylinder head assembly. TEST the system for normal operation after the repair.
  • Weak or broken valve spring
  • INSTALL a new valve spring. TEST the system for normal operation after the repair.
  • Worn or damaged cam
  • INSTALL a new camshaft. TEST the system for normal operation after the repair.
  • Damaged head gasket
  • INSTALL a new head gasket. TEST the system for normal operation after the repair.
  • Cracked or distorted cylinder head
  • INSTALL a new cylinder head assembly. TEST the system for normal operation after the repair.
  • Damaged, worn or sticking piston ring(s)
  • INSTALL a new piston ring(s). TEST the system for normal operation after the repair.
  • Worn or damaged piston
  • INSTALL a new piston and piston pin. TEST the system for normal operation after the repair.
  • Engine emits excessive smoke (black/blue/white)
  • Clogged Air Cleaner (ACL) element
  • Incorrect type or grade of oil
  • DRAIN and FILL with specified oil.
  • Blocked or restricted turbocharger oil drain pipes
  • INSPECT the turbocharger oil drain pipes. REPAIR as necessary. TEST the system for normal operation after the repair.
  • Damaged/restricted or leaking turbocharger intake tube assembly
  • REPAIR or INSTALL a new tube as necessary. TEST the system for normal operation after the repair.
  • Engine wear (piston rings, valve guides)
  • REPAIR as necessary. TEST the system for normal operation after the repair.
  • Plugged crankcase ventilation system
  • Visually INSPECT the crankcase ventilation system.
  • Turbocharger oil seals leaking
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