| Condition | Possible Cause | Action |
|---|---|---|
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Hard starting (Engine cranks OK)
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Faulty ignition coil
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Faulty CMP sensing rotor or CKP sensing rotor
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Faulty idle air control system
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Faulty ECT sensor, TP sensor, CKP sensor, CMP sensor or MAP sensor
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Fuel pressure out of specification
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Faulty fuel injector
|
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Faulty ECM
|
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Malfunctioning PCV system
|
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Low compression
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Improper valve lash
|
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Improper valve timing
|
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Compression leak from valve seat
|
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Sticky valve stem
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Weak or damaged valve springs
|
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Compression leak at cylinder head gasket
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Sticking or damaged piston ring
|
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Worn piston, ring or cylinder
|
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Engine has no power
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Engine overheating
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Condition “Engine overheating”
|
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Faulty ignition coil
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Faulty knock sensor
|
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Fuel pressure out of specification
|
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Faulty injector
|
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Faulty TP sensor, ECT sensor or MAP sensor
|
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Faulty ECM
|
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Malfunctioning EGR valve (if equipped)
|
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Maladjusted accelerator cable play
|
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Low compression
|
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Dragging brakes
|
Condition “Dragging brakes” in
Brakes Symptom Diagnosis
|
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Slipping clutch
|
Condition “Slipping clutch” in
Clutch System Symptom Diagnosis:M13A Model
|
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Improper engine idling or engine fails to idle
|
Faulty ignition coil
|
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Engine overheating
|
Condition “Engine overheating”
|
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Fuel pressure out of specification
|
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Faulty idle air control system
|
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Faulty evaporative emission control system
|
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Faulty injector
|
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Faulty ECT sensor, TP sensor or MAP sensor
|
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Malfunctioning PCV system
|
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Faulty ECM
|
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Faulty EGR system (if equipped)
|
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Low compression
|
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Engine hesitates (Momentary lack of response as the accelerator is depressed. Can occur at all vehicle speeds. Usually most severe when first trying to make the vehicle move, as from a stop sign.)
|
Faulty ignition coil
|
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Engine overheating
|
Condition “Engine overheating”
|
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Fuel pressure out of specification
|
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|
Faulty injector
|
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Faulty TP sensor, ECT sensor or MAP sensor
|
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Faulty ECM
|
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Malfunctioning EGR valve (if equipped)
|
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Low compression
|
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Surges (Engine power variation under steady throttle or cruise. Feels like the vehicle speeds up and down with no change in the accelerator pedal.)
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Faulty ignition coil or high-tension cord
|
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Variable fuel pressure
|
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Faulty MAP sensor
|
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Faulty injector
|
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|
Faulty ECM
|
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Malfunctioning EGR valve (if equipped)
|
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|
Excessive detonation (The engine makes sharp metallic knocks that change with throttle opening. Sounds like pop corn popping.)
|
Engine overheating
|
Condition “Engine overheating”
|
|
Faulty spark plug
|
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Clogged fuel filter and fuel lines
|
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Malfunctioning EGR valve (if equipped)
|
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Poor performance of knock sensor, ECT sensor or MAP sensor
|
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Faulty injector
|
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Faulty ECM
|
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Excessive combustion chamber deposits
|
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Overheating
|
Inoperative thermostat
|
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Faulty A/C condenser fan motor or its circuit
|
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Faulty radiator cooling fan clutch
|
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Loose or slip water pump belt
|
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Poor water pump performance
|
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Clogged or leaky radiator
|
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Improper engine oil grade
|
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Clogged oil filter or oil strainer
|
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Poor oil pump performance
|
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Dragging brakes
|
Condition “Dragging brakes” in
Brakes Symptom Diagnosis
|
|
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Slipping clutch
|
Condition “Slipping clutch” in
Clutch System Symptom Diagnosis:M13A Model
|
|
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Blown cylinder head gasket
|
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Poor gasoline mileage
|
Faulty ignition coil
|
|
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Fuel pressure out of specification
|
||
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Faulty TP sensor, ECT sensor or MAP sensor
|
||
|
Faulty injector
|
||
|
Faulty ECM
|
||
|
Malfunctioning EGR valve (if equipped)
|
||
|
High idle speed
|
Condition “Improper engine idling or engine fails to idle”
|
|
|
Low compression
|
||
|
Poor valve seating
|
||
|
Dragging brakes
|
Condition “Dragging brakes” in
Brakes Symptom Diagnosis
|
|
|
Slipping clutch
|
Condition “Slipping clutch” in
Clutch System Symptom Diagnosis:M13A Model
|
|
|
Thermostat out of order
|
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|
Improper tire pressure
|
||
|
Excessive engine oil consumption
|
Sticky piston ring
|
|
|
Worn piston and cylinder
|
||
|
Worn piston ring groove and ring
|
||
|
Improper location of piston ring gap
|
||
|
Worn or damaged valve stem seal
|
||
|
Worn valve stem
|
||
|
Low oil pressure
|
Improper oil viscosity
|
|
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Malfunctioning oil pressure switch
|
||
|
Clogged oil strainer
|
||
|
Functional deterioration of oil pump
|
||
|
Worn oil pump relief valve
|
||
|
Excessive clearance in various sliding parts
|
||
|
Engine noise
NOTE:
Before checking the mechanical noise, make sure that:
•
Ignition timing is properly adjusted.
• Specified spark plug is used. • Specified fuel is used. |
Improper valve lash
|
|
|
Worn valve stem and guide
|
||
|
Weak or broken valve spring
|
||
|
Warped or bent valve
|
||
|
Loose camshaft housing bolts
|
||
|
Worn piston, ring and cylinder bore
|
||
|
Worn crank pin bearing
|
||
|
Worn crank pin
|
||
|
Loose connecting rod nuts
|
||
|
Low oil pressure
|
Condition “Low Oil Pressure”
|
|
|
Worn crankshaft journal bearing
|
||
|
Worn crankshaft journal
|
||
|
Loose lower crankcase (bearing cap) bolts
|
||
|
Excessive crankshaft thrust play
|
||
|
Excessive hydrocarbon (HC) emission or Excessive carbon monoxide (CO) emission
|
Faulty ignition coil
|
|
|
Fuel pressure out of specification
|
||
|
Lead contamination of three way catalytic converter
|
Check for absence of filler neck restrictor.
|
|
|
Malfunctioning PCV system
|
||
|
Faulty EVAP control system
|
||
|
Closed loop system (A/F feed back compensation) fails
– Faulty TP sensor
– Faulty ECT sensor or MAP sensor
– Faulty oxygen sensor
|
||
|
Faulty injector
|
||
|
Faulty ECM
|
||
|
Low compression
|
||
|
Excessive nitrogen oxides (NOx) emission
|
Fuel pressure out of specification
|
|
|
Lead contamination of three way catalytic converter
|
Check for absence of filler neck restrictor
|
|
|
Closed loop system (A/F feed back compensation) fails
– Faulty TP sensor
– Faulty ECT sensor or MAP sensor
– Faulty oxygen sensor
|
||
|
Faulty injector
|
||
|
Faulty ECM
|
||
|
Faulty EGR system (if equipped)
|