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Engine Symptom DiagnosisS6RW0D1104010
Perform troubleshooting referring to the followings when ECM has detected no DTC and no abnormality has been
found in “Visual Inspection” and “Engine Basic Inspection”.
Condition Possible cause Correction / Reference Item
Hard starting (Engine
cranks OK)Faulty spark plug“Spark Plug Inspection in Section 1H”
Leaky high-tension cord“High-Tension Cord Inspection in Section 1H”
Loose connection or disconnection of
high-tension cord(s) or lead wire(s)“High-Tension Cord Removal and Installation
in Section 1H”
Faulty ignition coil“Ignition Coil Assembly (Including Ignitor)
Inspection in Section 1H”
Dirty or clogged fuel hose or pipe“Fuel Pressure Check”
Malfunctioning fuel pump“Fuel Pressure Check”
Air drawn in through intake manifold
gasket or throttle body gasket
Faulty electric throttle body assembly“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly“Accelerator Pedal Position (APP) Sensor
Assembly Inspection in Section 1C”
Faulty ECT sensor or MAF sensor“Engine Coolant Temperature (ECT) Sensor
Inspection in Section 1C” or “Intake Air
Temperature (IAT) Sensor Inspection in
Section 1C”
Faulty ECM
Low compression“Compression Check in Section 1D”
Poor spark plug tightening or faulty
gasket“Spark Plug Removal and Installation in
Section 1H”
Compression leak from valve seat“Valves and Valve Guides Inspection in
Section 1D”
Sticky valve stem“Valves and Valve Guides Inspection in
Section 1D”
Weak or damaged valve springs“Valve Spring Inspection in Section 1D”
Compression leak at cylinder head
gasket“Cylinder Head Inspection in Section 1D”
Sticking or damaged piston ring“Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn piston, ring or cylinder“Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Malfunctioning PCV valve“PCV Valve Inspection in Section 1B”
Camshaft position control (VVT) system
out of order (for engine with VVT
system)“Oil Control Valve Inspection (For Engine with
VVT) in Section 1D”
Faulty EGR system“EGR System Inspection (If Equipped) in
Section 1B”
Low oil pressureImproper oil viscosity“Engine Oil and Filter Change in Section 0B”
Malfunctioning oil pressure switch“Oil Pressure Switch Inspection in Section 9C”
Clogged oil strainer“Oil Pan and Oil Pump Strainer Cleaning in
Section 1E”
Functional deterioration of oil pump“Oil Pump Inspection in Section 1E”
Worn oil pump relief valve“Oil Pump Inspection in Section 1E”
Excessive clearance in various sliding
parts
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Engine overheatingInoperative thermostat“Thermostat Inspection in Section 1F”
Poor water pump performance“Water Pump Inspection in Section 1F”
Clogged or leaky radiator“Radiator On-Vehicle Inspection and Cleaning
in Section 1F”
Improper engine oil grade“Engine Oil and Filter Change in Section 0B”
Clogged oil filter or oil strainer“Oil Pressure Check in Section 1E”
Poor oil pump performance“Oil Pressure Check in Section 1E”
Faulty radiator cooling fan control
system“Radiator Cooling Fan Control System Check”
Dragging brakesCondition “Dragging brakes” in “Brakes
Symptom Diagnosis in Section 4A”
Slipping clutch (for M/T model)Condition “Slipping clutch” in “Clutch System
Symptom Diagnosis in Section 5C” for M/T
model
Blown cylinder head gasket“Cylinder Head Inspection in Section 1D”
Air mixed in cooling system
Poor gasoline mileageLeaks or loose connection of high-
tension cord“High-Tension Cord Removal and Installation
in Section 1H”
Faulty spark plug (improper gap, heavy
deposits and burned electrodes, etc.)“Spark Plug Inspection in Section 1H”
Malfunctioning EGR valve“EGR Valve Inspection (If Equipped) in Section
1B”
High idle speedCondition “Improper engine idling or engine
fails to idle”
Poor performance of ECT sensor, MAF
sensor“Engine Coolant Temperature (ECT) Sensor
Inspection in Section 1C”, or “Intake Air
Temperature (IAT) Sensor Inspection in
Section 1C”
Faulty electric throttle body assembly“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly“Accelerator Pedal Position (APP) Sensor
Assembly Inspection in Section 1C”
Faulty fuel injector(s)“Fuel Injector Circuit Check”
Faulty ECM
Low compression“Compression Check in Section 1D”
Poor valve seating“Valves and Valve Guides Inspection in
Section 1D”
Dragging brakesCondition “Dragging brakes” in “Brakes
Symptom Diagnosis in Section 4A”
Slipping clutch (for M/T model)Condition “Slipping clutch” in “Clutch System
Symptom Diagnosis in Section 5C” for M/T
model
Thermostat out of order“Thermostat Inspection in Section 1F”
Improper tire pressure“Tires Description in Section 2D”
Camshaft position control (VVT) system
out of order (for engine with VVT
system)“Oil Control Valve Inspection (For Engine with
VVT) in Section 1D”
Excessive engine oil
consumption – Oil
leakageBlown cylinder head gasket“Cylinder Head Inspection in Section 1D”
Leaky camshaft oil seals“Camshaft, Tappet and Shim Inspection in
Section 1D” Condition Possible cause Correction / Reference Item
Downloaded from www.Manualslib.com manuals search engine 1A-48 Engine General Information and Diagnosis:
Excessive engine oil
consumption – Oil
entering combustion
chamberSticky piston ring“Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn piston and cylinder“Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn piston ring groove and ring“Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Improper location of piston ring gap“Pistons, Piston Rings, Connecting Rods and
Cylinders Disassembly and Assembly in
Section 1D”
Worn or damaged valve stem seal“Valves and Valve Guides Inspection in
Section 1D”
Worn valve stem“Valves and Valve Guides Inspection in
Section 1D”
Engine hesitates –
Momentary lack of
response as accelerator
is depressed. Can occur
at all vehicle speeds.
Usually most severe when
first trying to make
vehicle move, as from a
stop sign.Spark plug faulty or plug gap out of
adjustment“Spark Plug Inspection in Section 1H”
Leaky high-tension cord“High-Tension Cord Inspection in Section 1H”
Fuel pressure out of specification“Fuel Pressure Check”
Malfunctioning EGR valve“EGR Valve Inspection (If Equipped) in Section
1B”
Poor performance of ECT sensor or
MAF sensor, “Engine Coolant Temperature (ECT) Sensor
Inspection in Section 1C” or “Intake Air
Temperature (IAT) Sensor Inspection in
Section 1C”
Faulty electric throttle body assembly“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly“Accelerator Pedal Position (APP) Sensor
Assembly Inspection in Section 1C”
Faulty fuel injector“Fuel Injector Circuit Check”
Faulty ECM
Engine overheatingCondition “Engine overheating”
Low compression“Compression Check in Section 1D”
Camshaft position control (VVT) system
out of order (for engine with VVT
system)“Oil Control Valve Inspection (For Engine with
VVT) in Section 1D”
Surge – Engine power
variation under steady
throttle or cruise. Feels
like vehicle speeds up
and down with no change
in accelerator pedal.Leaky or loosely connected high-tension
cord“High-Tension Cord Removal and Installation
in Section 1H”
Faulty spark plug (excess carbon
deposits, improper gap, burned
electrodes, etc.)“Spark Plug Inspection in Section 1H”
Variable fuel pressure“Fuel Pressure Check”
Kinky or damaged fuel hose and lines
Faulty fuel pump (clogged fuel filter)
Malfunctioning EGR valve“EGR Valve Inspection (If Equipped) in Section
1B”
Poor performance of MAF sensor“Intake Air Temperature (IAT) Sensor
Inspection in Section 1C”
Faulty fuel injector“Fuel Injector Circuit Check”
Faulty ECM
Faulty electric throttle body assembly“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly“Accelerator Pedal Position (APP) Sensor
Assembly Inspection in Section 1C” Condition Possible cause Correction / Reference Item
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Excessive detonation –
Engine makes
continuously sharp
metallic knocks that
change with throttle
opening. Sounds like pop
corn popping.Faulty spark plug“Spark Plug Inspection in Section 1H”
Loose connection of high-tension cord“High-Tension Cord Removal and Installation
in Section 1H”
Engine overheatingCondition “Engine overheating”
Clogged fuel filter (faulty fuel pump) or
fuel lines“Fuel Pressure Check” or “Fuel Pump and Its
Circuit Check”
Air drawn in through intake manifold or
throttle body gasket
Malfunctioning EGR valve“EGR Valve Inspection (If Equipped) in Section
1B”
Poor performance of knock sensor, ECT
sensor or MAF sensor“DTC P0327 / P0328: Knock Sensor Circuit
Low / High”, “Engine Coolant Temperature
(ECT) Sensor Inspection in Section 1C” or
“Intake Air Temperature (IAT) Sensor
Inspection in Section 1C”
Faulty fuel injector(s)“Fuel Injector Circuit Check”
Faulty ECM
Excessive combustion chamber
deposits“Cylinders, Pistons and Piston Rings
Inspection in Section 1D” and/or “Piston Pins
and Connecting Rods Inspection in Section
1D”
Camshaft position control (VVT) system
out of order (for engine with VVT
system)“Oil Control Valve Inspection (For Engine with
VVT) in Section 1D”
Engine has no powerFaulty spark plug“Spark Plug Inspection in Section 1H”
Faulty ignition coil with ignitor“Ignition Coil Assembly (Including Ignitor)
Inspection in Section 1H”
Leaks, loose connection or
disconnection of high-tension cord“High-Tension Cord Removal and Installation
in Section 1H”
Faulty knock sensor“DTC P0327 / P0328: Knock Sensor Circuit
Low / High”
Clogged fuel hose or pipe“Fuel Pressure Check”
Malfunctioning fuel pump“Fuel Pump and Its Circuit Check”
Air drawn in through intake manifold
gasket or throttle body gasket
Engine overheatingCondition “Engine overheating”
Malfunctioning EGR valve“EGR Valve Inspection (If Equipped) in Section
1B”
Poor performance of ECT sensor or
MAF sensor“Engine Coolant Temperature (ECT) Sensor
Inspection in Section 1C” or “Intake Air
Temperature (IAT) Sensor Inspection in
Section 1C”
Faulty electric throttle body assembly“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly“Accelerator Pedal Position (APP) Sensor
Assembly Inspection in Section 1C”
Faulty fuel injector(s)“Fuel Injector Circuit Check”
Faulty ECM
Dragging brakesCondition “Dragging brakes” in “Brakes
Symptom Diagnosis in Section 4A”
Slipping clutch (for M/T model)Condition “Slipping clutch” in “Clutch System
Symptom Diagnosis in Section 5C” (for M/T
model)
Low compression“Compression Check in Section 1D”
Camshaft position control (VVT) system
out of order (for engine with VVT
system)“Oil Control Valve Inspection (For Engine with
VVT) in Section 1D” Condition Possible cause Correction / Reference Item
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Excessive hydrocarbon
(HC) emission or carbon
monoxide (CO)Faulty spark plug“Spark Plug Inspection in Section 1H”
Leaky or disconnected high-tension cord“High-Tension Cord Removal and Installation
in Section 1H”
Faulty ignition coil with ignitor“Ignition Coil Assembly (Including Ignitor)
Inspection in Section 1H”
Low compression“Compression Check in Section 1D”
Lead contamination of three way
catalytic converterCheck for absence of filler neck restrictor.
Faulty evaporative emission control
system“EVAP Canister Purge Inspection in Section
1B”
Fuel pressure out of specification“Fuel Pressure Check”
Closed loop system (A/F feedback
compensation) fails (Poor performance
of ECT sensor or MAF sensor)“Engine Coolant Temperature (ECT) Sensor
Inspection in Section 1C” or “Intake Air
Temperature (IAT) Sensor Inspection in
Section 1C”
Faulty electric throttle body assembly“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly“Accelerator Pedal Position (APP) Sensor
Assembly Inspection in Section 1C”
Faulty injector(s)“Fuel Injector Circuit Check”
Faulty ECM
Engine not at normal operating
temperature
Clogged air cleaner“Air Cleaner Filter Inspection and Cleaning in
Section 1D”
Vacuum leaks“Engine Vacuum Check in Section 1D”
Camshaft position control (VVT) system
out of order (for engine with VVT
system)“Oil Control Valve Inspection (For Engine with
VVT) in Section 1D”
Excessive nitrogen
oxides (NOx) emissionImproper ignition timing“Ignition Timing Inspection in Section 1H”
Lead contamination of catalytic
converterCheck for absence of filler neck restrictor.
Faulty EGR system“EGR System Inspection (If Equipped) in
Section 1B”
Fuel pressure out of specification“Fuel Pressure Check”
Closed loop system (A/F feedback
compensation) fails (Poor performance
of ECT sensor or MAF sensor)“Engine Coolant Temperature (ECT) Sensor
Inspection in Section 1C” or “Intake Air
Temperature (IAT) Sensor Inspection in
Section 1C”
Faulty electric throttle body assembly“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly“Accelerator Pedal Position (APP) Sensor
Assembly Inspection in Section 1C”
Faulty injector(s)“Fuel Injector Circuit Check”
Faulty ECM
Camshaft position control (VVT) system
out of order (for engine with VVT
system)“Oil Control Valve Inspection (For Engine with
VVT) in Section 1D” Condition Possible cause Correction / Reference Item
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-201
Fuel Pressure CheckS6RW0D1104076
System Diagram
Special tool
(A): 09912–58442
(B): 09912–58432
(C): 09912–58490
Troubleshooting
NOTE
Before using following flow, check to make sure that battery voltage is higher than 11 V. If battery
voltage is low, pressure becomes lower than specification even if fuel pump and line are in good
condition.
I3RM0A110081-01
1. Injector 2. Delivery pipe 3. Fuel filter and fuel pump
Step Action Yes No
1Fuel pressure check
1) Check fuel pressure referring to “Fuel Pressure
Inspection in Section 1G”.
Is check result satisfactory?Go to Step 2. Go to Step 5.
2Fuel pressure check
1) Start engine and warm it up to normal operating
temperature.
2) Keep engine speed at 4000 rpm.
Does fuel pressure show about the same value as Step 1?Go to Step 3. Go to Step 8.
3Fuel line check
1) Check fuel pipe, fuel hose and joint for fuel leakage.
Are they in good condition?Go to Step 4. Repair or replace
defective part.
Downloaded from www.Manualslib.com manuals search engine 1A-202 Engine General Information and Diagnosis:
A/C Condenser Cooling Fan Control System InspectionS6RW0D1104077
Wiring Diagram4Fuel line check
1) Check fuel pipe, fuel hose and joint for damage or
deform.
Are they in good condition?Faulty fuel pressure
regulator.Repair or replace
damaged or damaged
part.
5Was fuel pressure higher than specification in Step 1?Go to Step 6. Go to Step 7.
6Fuel line check
1) Check fuel pipe, fuel hose and joint for damage or
deform.
Are they in good condition?Faulty fuel pressure
regulator.Repair or replace
damaged or damaged
part.
7Fuel pump operating sound check
1) Remove fuel filler cap and then turn ON ignition switch.
Can you hear operating sound?Go to Step 8. Faulty fuel pump.
8Fuel line check
1) Check fuel pipe, fuel hose and joint for damage or
deform.
Are they in good condition?Clogged fuel filter, faulty
fuel pump, faulty fuel
pressure regulator or
fuel leakage from hose
connection in fuel tank.Repair or replace
defective part. Step Action Yes No
E01C01
3 4
18 19 5 6 7 10 11
17 20
47 46 49 50 51 21 22
5216 259
24 14
29
55 57 54 53 59
60 582
26 27 28 15
30
56 4832 31 34 35 36 37 40 42 39 38 44
45 43 41 331 12 13
238 3 4
18 19 5 6 7 10 11
17 20
47 46 49 50 51 21 22
5216 259
24 14
29
55 57 54 53 59
60 582
26 27 28 15
30
56 4832 31 34 35 36 37 40 42 39 38 44
45 43 41 331 12 13
238
BLK/WHT
WHT
1
GRN
27
E01-29
10
89
REDBLK
3
5BLK/WHT
RED/BLKE01-58
WHT
4E01-47 GRY
BLU/YEL
6
C01-58
C01-15 C01-30
BLK/ORN
BLKBLKE01-31BLK
I6RW0D110055-01
1. Individual circuit fuse box No.1 5. A/C condenser cooling fan motor 9. “A/C” fuse
2. Ignition switch 6. A/C compressor 10. “IG COIL” fuse
3. A/C condenser cooling fan relay 7. ECM
4. A/C compressor relay 8. “FI” fuse
Downloaded from www.Manualslib.com manuals search engine Engine Mechanical: 1D-3
Camshaft Position Control (VVT Variable Valve Timing) System DescriptionS6RW0D1401002
System Description
The VVT system is an electronic control system which continuously vary and optimize the intake valve timing in
response to the engine operating condition.
The optimized intake valve timing produce such an air intake with high efficiency that both the higher power generation
and lower fuel consumption can be attained in the whole engine speed range from low to high. In the area of the
average engine load, low emission of nitrogen oxides (NOx) and high fuel efficiency can also be attained by making
the valve opening overlap between the intake and exhaust valves longer.
For the brief of the system operation, the intake valve timing is varied by the cam timing sprocket (1) which varies the
rotational phase between the intake camshaft (3) and sprocket. The rotor (2) in the cam timing sprocket is actuated by
switching or adjusting the hydraulic pressure applied to the chambers for the timing advancing (7) and/or retarding (6).
To switch or adjust the hydraulic pressure appropriately, ECM operates the oil control valve (12) with detecting the
engine speed, intake air value, throttle opening, engine coolant temperature and camshaft position (angle).
1
4
5
10
8
9
2
7
6
12
11
3
60˚ (variable angle)
Most retarded timing Most advanced timing
Exhaust valveIntake valve
Crank angle
Overlap of valves
Valve lift
I5RW0C140002-01
4. Oil passage to chamber for timing retarding 8. Oil filter 10. Oil pan
5. Oil passage to chamber for timing advancing 9. Oil pump 11. Control signal from ECM