2006 SUZUKI SX4 Engine General Information and Diagnosis

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THROTTLE MOTOR RELAY (ON/OFF)
ON: Throttle actuator (motor) control activated by ECM.
OF: Throttle actuator (motor) control stopped by ECM.
VEHICLE SPEED (km/h, mph)
It is computed based on pulse signals from front wheel
speed sensor (RH, LH) (for M/T model) or output shaft
speed sensor (VSS) (for A/T model).INJ PULSE WIDTH (FUEL INJECTION PULSE WIDTH,
msec.)
This parameter indicates time of the injector drive (valve
opening) pulse which is output from ECM (but injector
drive time of NO.1 cylinder for multiport fuel injection).
Visual InspectionS6RW0D1104008
Visually check the following parts and systems.
Engine Basic InspectionS6RW0D1104009
This check is very important for troubleshooting when ECM has detected no DTC and no abnormality has been found
in “Visual Inspection”.
Follow the flow carefully.Inspection item Reference section
• Engine oil – level, leakage “Engine Oil and Filter Change in Section 0B”
• Engine coolant – level, leakage “Coolant Level Check in Section 1F”
• Fuel – level, leakage“Fuel Lines and Connections Inspection in
Section 0B”
• Air cleaner element – dirt, clogging “Air Cleaner Filter Inspection in Section 0B”
• Battery – fluid level, corrosion of terminal“Battery Dismounting and Remounting in
Section 1J”
• Water pump belt – tension damage“Accessory Drive Belt Inspection in Section
0B”
• Throttle valve – operating sound“Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
• Vacuum hoses of air intake system – disconnection, looseness,
deterioration, bend“Vacuum Hose Inspection in Section 1B”
• Connectors of electric wire harness – disconnection, friction
• Fuses – burning
• Parts – installation, bolt – looseness
• Parts – deformation
• Other parts that can be checked visually
Also check the following items at engine start, if possible
• Malfunction indicator lamp – Operation “Malfunction Indicator Lamp (MIL) Check”
• Charge warning lamp – Operation “Generator Symptom Diagnosis in Section 1J”
• Engine oil pressure warning lamp – Operation “Oil Pressure Switch Inspection in Section 9C”
• Engine coolant temp. meter – Operation“Engine Coolant Temperature (ECT) Sensor
Inspection in Section 1C”
• Fuel level meter – Operation “Fuel Level Sensor Inspection in Section 9C”
• Tachometer – Operation
• Abnormal air being inhaled from air intake system
• Exhaust system – leakage of exhaust gas, noise
• Other parts that can be checked visually
Step Action Yes No
1Was “Engine and Emission Control System Check”
performed?Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2Check battery voltage
Is it 11 V or more?Go to Step 3. Charge or replace
battery.
3Is vehicle equipped with keyless start control system?Go to Step 4. Go to Step 5.

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4Check keyless start control system malfunction
1) Check keyless start control system referring to “Keyless
Start System Operation Inspection in Section 10E”.
Is check result satisfactory?Go to Step 5. Keyless start control
system malfunction.
5Is engine cranked?Go to Step 6. Go to “Cranking System
Symptom Diagnosis in
Section 1I”.
6Does engine start?Go to Step 7. Go to Step 9.
7Check idle speed
1) Check engine idle speed referring to “Idle Speed and
IAC Throttle Valve Opening Inspection”.
Is check result as specified?Go to Step 8. Go to “Engine Symptom
Diagnosis”.
8Check ignition timing
1) Check ignition timing referring to “Ignition Timing
Inspection in Section 1H”.
Is check result as specified?Go to “Engine Symptom
Diagnosis”.Check ignition control
related parts referring to
“Ignition Timing
Inspection in Section
1H”.
9Check immobilizer system malfunction
1) Check immobilizer indicator lamp for flashing.
Is it flashing when ignition switch is turned to ON position?Go to “DTC Check in
Section 10C”.Go to Step 10.
10Check fuel supply
1) Check to make sure that enough fuel is filled in fuel tank.
2) Turn ON ignition switch for 2 seconds and then OFF.
3) Repeat Step 2) a few times.
Is fuel pressure felt from fuel feed hose when ignition switch
is turned ON?Go to Step 12. Go to Step 11.
11Check fuel pump for operation
Was fuel pump operating sound heard from fuel filler for
about 2 seconds after ignition switch ON and stop?Go to “Fuel Pressure
Check”.Go to “Fuel Pump and
Its Circuit Check”.
12Check ignition spark
1) Check ignition spark referring to “Ignition Spark Test in
Section 1H”.
Is it in good condition?Go to Step 13. Go to “Ignition System
Symptom Diagnosis in
Section 1H”.
13Check fuel injector circuit
1) Check fuel injector circuit referring to “Fuel Injector
Circuit Check.”
Is it in good condition?Go to “Engine Symptom
Diagnosis”.Go to “Fuel Injector
Circuit Check”. Step Action Yes No
I5RW0A110014-01

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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 noise – Valve
noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is
used.
• Specified fuel is used.

Improper valve lash“Camshaft, Tappet and Shim Inspection in
Section 1D”
Worn valve stem and guide“Valves and Valve Guides Inspection in
Section 1D”
Weak or broken valve spring“Valve Spring Inspection in Section 1D”
Warped or bent valve“Valves and Valve Guides Inspection in
Section 1D”
Engine noise – Piston,
ring and cylinder noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is
used.
• Specified fuel is used.

Worn piston, ring and cylinder bore“Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Engine noise –
Connecting rod noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is
used.
• Specified fuel is used.

Worn piston, ring and cylinder bore“Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn rod bearing“Crank Pin and Connecting Rod Bearings
Inspection in Section 1D”
Worn crank pin“Crank Pin and Connecting Rod Bearings
Inspection in Section 1D”
Loose connecting rod nuts“Pistons, Piston Rings, Connecting Rods and
Cylinders Removal and Installation in Section
1D”
Low oil pressureCondition “Low oil pressure”
Engine noise –
Crankshaft noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is
used.
• Specified fuel is used.

Low oil pressureCondition “Low oil pressure”
Worn bearing“Main Bearings Inspection in Section 1D”
Worn crankshaft journal“Crankshaft Inspection in Section 1D”
Loose bearing cap bolts“Main Bearings, Crankshaft and Cylinder Block
Removal and Installation in Section 1D”
Excessive crankshaft thrust play“Crankshaft Inspection in Section 1D” Condition Possible cause Correction / Reference Item

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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

Downloaded from www.Manualslib.com manuals search engine 1A-50 Engine General Information and Diagnosis:
Improper engine idling or
engine fails to idleFaulty 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”
Fuel pressure out of specification“Fuel Pressure Check”
Leaky manifold, throttle body, or cylinder
head gasket
Malfunctioning EGR valve“EGR Valve Inspection (If Equipped) in Section
1B”
Faulty evaporative emission control
system“EVAP Canister Purge Inspection in Section
1B”
Faulty EGR system“EGR System Inspection (If Equipped) in
Section 1B”
Faulty fuel injector(s)“Fuel Injector Circuit Check”
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 ECM
Loose connection or disconnection of
vacuum hoses
Malfunctioning PCV valve“PCV Valve Inspection in Section 1B”
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” Condition Possible cause Correction / Reference Item