2006 SUZUKI SX4 Fuel System

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-47
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

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-49
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

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-51
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 1A-92 Engine General Information and Diagnosis:
DTC P0131 / P0132: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-1)S6RW0D1104031
Wiring Diagram
DTC Detecting Condition and Trouble Area
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
11
GRN
39
E01-29
WHT
ORN
BLK/WHT
BLKC01-46
C01-10
C01-57
6
7
10
BLK
BLUWHT
BLK/RED
1
4
5
8
12
I6RW0D110027-01
1. Main fuse box 4. Junction block assembly 7. Heater 10. To HO2S-2
2. Shield wire 5. “IG COIL” fuse 8. To HO2S-2 heater 11. Individual circuit fuse box No.1
3. Ignition switch 6. HO2S-1 9. ECM 12. “IGN” fuse
DTC detecting condition Trouble area
DTC P0131:
Maximum HO2S voltage is lower than specified voltage.
(2 driving cycle detection logic, monitoring once/1 driving)
DTC P0132:
Minimum HO2S voltage is higher than specified voltage.
(2 driving cycle detection logic, monitoring once/1 driving)• HO2S-1 circuit
•HO2S-1
• Fuel system
•ECM
• Fuel shortage
• Exhaust system
• Air intake system

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-93
DTC Confirmation Procedure
WARNING!
• When performing a road test, select a place where there is no traffic or possibility of a traffic
accident and be very careful during testing to avoid occurrence of an accident.
• Road test should be carried out by 2 persons, a driver and a tester, on a level road.

NOTE
Check to make sure that following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Intake air temperature at engine start: –10 °C (14 °F) to 80 °C (176 °F)
• Intake air temperature: –10 °C (14 °F) to 70 °C (158 °F)
• Engine coolant temperature: 70 °C (158 °F) or more
• Altitude (barometric pressure): 2500 m, 8200 ft or less (560 mmHg, 74.4 kPa or more)

1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature.
4) Drive vehicle at 40 mph (60 km/h) or higher. (engine speed: 2500 – 3000 r/min.)
5) Keep above vehicle speed for 6 min. or more. (Throttle valve opening is kept constant in this step.)
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (with fuel cut for 3 sec. or more)
and then stop vehicle.
7) For european market model, check whether O2 sensor readiness/monitoring test has completed or not by using
scan tool.
If O2 sensor readiness/monitoring test has not completed, check vehicle conditions (environmental) and repeat
Step 3) through 6).
8) Check DTC and pending DTC.
DTC Troubleshooting
NOTE
Before this troubleshooting is performed, read the precautions for DTC troubleshooting referring to
“Precautions for DTC Troubleshooting”.

Step Action Yes No
1Was “Engine and Emission Control System Check”
performed?Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2Is there DTC(s) other than HO2S-1?Go to applicable DTC
diag. flow.Go to Step 3.
3HO2S-1 signal check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Warm up engine to normal operating temperature and
keep it at 2000 r/min. for 60 sec.
3) Repeat racing engine (Repeat depressing accelerator
pedal 5 to 6 times continuously to enrich A/F mixture and
take foot off from pedal to enlean it).
Does HO2S-1 output voltage deflect between below 0.3 V
and over 0.6 V repeatedly?Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”. If check result is
OK, go to Step 9.Go to Step 4.

Downloaded from www.Manualslib.com manuals search engine 1A-94 Engine General Information and Diagnosis:
4HO2S-1 ground check
1) Disconnect connector from HO2S-1 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-1 connector at
“BLK/RED”, “WHT”, “BLK/WHT” and “ORN” wire
terminals.
3) If connections are OK, measure resistance between
“ORN” wire terminal of HO2S-1 connector and engine
ground.
Is measured resistance less than 5
Ω?Go to Step 5. “ORN” wire is open or
high resistance circuit.
Poor “C01-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
5Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its bracket with ECM connectors
connected.
3) Measure resistance between “WHT” wire terminal of
HO2S-1 connector and “C01-10” terminal of ECM
connector.
Is resistance less than 5
Ω?Go to Step 6. “WHT” wire is high
resistance circuit or
open circuit. Poor “C01-
10” terminal connection.
Faulty ECM ground. If
they are OK, substitute
a known-good ECM and
recheck.
6Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turn OFF.
2) Measure resistance between “WHT” wire terminal of
HO2S-1 connector and vehicle body ground.
Is resistance infinity?Go to Step 7. “WHT” wire is shorted to
ground circuit.
7HO2S-1 signal circuit check
1) Measure voltage between “WHT” wire terminal of HO2S-
1 connector and vehicle body ground.
Is voltage 0 V?Go to Step 8. “WHT” wire is shorted to
other circuit.
8HO2S-1 heater circuit check
1) Check HO2S-1 heater circuit referring to “DTC P0031 /
P0032: HO2S Heater Control Circuit Low / High
(Sensor-1)”.
Is circuit in good condition?Go to Step 9. Repair HO2S-1 circuit.
9Exhaust system check
1) Check exhaust system for exhaust gas leakage.
Is it OK?Go to Step 4 in “DTC
P0171 / P0172: Fuel
System Too Lean /
Rich”.
If it is in good condition,
go to Step 10.Repair leakage of
exhaust system.
10Air intake system check
1) Check air intake system for clog or leak.
Is it OK?Replace HO2S-1
referring to “Heated
Oxygen Sensor (HO2S-
1 and HO2S-2)
Removal and
Installation (If Equipped)
in Section 1C”.
If DTC still exists,
substitute a known-
good ECM and recheck.Repair or replace air
intake system. Step Action Yes No