injector SUZUKI SWIFT 2007 2.G Service User Guide

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Scan Tool Data Definitions
COOLANT TEMP (ENGINE COOLANT
TEMPERATURE, °C, °F)
It is detected by engine coolant temp. sensor.
INTAKE AIR TEMP. ( °C, °F)
It is detected by intake air temp. sensor.
ENGINE SPEED (rpm)
It is computed by reference pulses from the camshaft
position sensor.
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 fo r multiport fuel injection).
DESIRED IDLE (DESIRED IDLE SPEED, rpm)
The Desired Idle Speed is an ECM internal parameter
which indicates the ECM requested idle. If the engine is
not running, this number is not valid.
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
Short term fuel trim valu e represents short term
corrections to the air/fuel mixture computation. A value
of 0 indicates no correction, a value greater than 0
means an enrichment correction, and a value less than 0
implies an enleanment correction. LONG FT B1 (LONG TERM FUEL TRIM, %)
Long term fuel trim value represents long term
corrections to the air/fuel mixture computation. A value
of 0 indicates no correction, a value greater than 0
means an enrichment correction, and a value less than 0
implies an enleanment correction.
TOTAL FUEL TRIM B1 (%)
The value of Total Fuel Trim is obtained by calculating
based on values of Short Term Fuel Trim and Long Term
Fuel Trim. This value indica
tes how much correction is
necessary to keep the air/fuel mixture stoichiometrical.
MAF (MASS AIR FLOW RATE, g/s, lb/min.)
It represents total mass of air entering intake manifold
which is measured by mass air flow sensor.
CALC LOAD (CALCULATED LOAD VALUE, %)
Engine load displayed as a percentage of maximum
possible load. Value is calculated mathematically using
the formula: actual (current) intake air volume ÷
maximum possible intake air volume × 100%
THROTTLE POS (ABSOLUTE THROTTLE POSITION,
%)
When throttle position sensor is at fully closed position,
throttle opening is indicated as 0 – 5% and 90 – 100%
full open position.
O2S SENSOR B1 S1 (HEA TED OXYGEN SENSOR-1,
V)
It indicates output voltage of HO2S-1 installed on
exhaust manifold (pre-catalyst).
)
TP SENSOR 2 VOLT Ignition switch ON after
warmed up engine Accelerator pedal released
1.4 – 1.8 V
Accelerator pedal depressed
fully 3.58 – 4.76 V
) APP SENSOR 1
VOLT Ignition switch ON after
warmed up engineAccelerator pedal released
0.5 – 0.9 V
Accelerator pedal depressed
fully 3.277 – 3.915 V
) APP SENSOR 2
VOLT Ignition switch ON after
warmed up engineAccelerator pedal released
1.3 – 1.7 V
Accelerator pedal depressed
fully 4.077 – 4.715 V
) ACCEL POSITION Ignition switch ON after
warmed up engine Accelerator pedal released
0 – 5%
Accelerator pedal depressed
fully 90 – 100%
) THROTTLE TARGET
POSI Ignition switch ON after
warmed up engineAccelerator pedal released
0 – 5%
Accelerator pedal depressed
fully 90 – 100%
) BATTERY
CURRENT At specified idle speed with no load after warming up
5.0 – 60.0 A
) GENERATOR CONT
DUTY (GENERATOR
CONTROL DUTY) At specified idle speed with no load after warming up
20.0 – 100.0%
) GENERATOR FIELD
DUTY (GENERATOR
FIELD COIL DUTY) At spe
cified idle speed with no load after warming up
20.0 – 100.0%
Scan tool data
Vehicle condition Normal condition /
reference values

Downloaded from www.Manualslib.com manuals search engine 1A-36 Engine General Information and Diagnosis:
O2S B1 S1 ACT (HEATED OXYGEN SENSOR-1,
ACTIVE / INACTIVE)
This parameter indicates activation condition of HO2S-1.
ACTIVE: Activating
INACTIVE: warming up or at stop
O2S SENSOR B1 S2 (HEATED OXYGEN SENSOR-2,
V)
It indicates output voltage of HO2S-2 installed on
exhaust pipe (post-catalyst). It is used to detect catalyst
deterioration.
O2S B1 S2 ACT (HEATED OXYGEN SENSOR-2,
ACTIVE / INACTIVE)
This parameter indicates acti vation condition of HO2S-2.
ACTIVE: Activating
INACTIVE: warming up or at stop
FUEL SYSTEM (FUEL SYSTEM STATUS)
Air/fuel ratio feedback loop status displayed as one of
the followings.
OPEN: Open-loop has not yet satisfied conditions to go
closed loop.
CLOSED: Closed-loop using oxygen sensor(s) as
feedback for fuel control.
OPEN-DRIVE COND: Open-loop due to driving
conditions (Power enrichment, etc.).
OPEN SYS FAULT: Open-loop due to detected system
fault.
MAP (MANIFOLD ABSOLUTE PRESSURE, in.Hg,
kPa)
This value indicates how much correction is necessary
to keep the air/fuel mixture stoichiometrical.
It is detected by manifold absolute pressure sensor.
BAROMETRIC PRESS (kPa, in.Hg)
This parameter represents a measurement of barometric
air pressure and is used for al titude correction of the fuel
injection quantity and IAC valve control.
STEP EGR FLOW DUTY (%)
This parameter indicates opening rate of EGR valve
which controls the amount of EGR flow.
FUEL CUT (ON/OFF)
ON: Fuel being cut (output signal to injector is stopped)
OFF: Fuel not being cut
A/C PRESSURE (A/C REFRIGERANT ABSOLUTE
PRESSURE, kPa)
This parameter indicates A/C refrigerant absolute
pressure calculated by ECM.
CLOSED THROTTLE PO S (CLOSED THROTTLE
POSITION, ON/OFF)
This parameter reads ON wh en throttle valve is fully
closed, or OFF when it is not fully closed. CANIST PRG DUTY (EVAP CANISTER PURGE FLOW
DUTY, %)
This parameter indicates valve ON (valve open) time
rate within a certain set cycle of EVAP canister purge
valve which controls the amount of EVAP purge.
IGNITION ADVANCE (IGNITION TIMING ADVANCE
FOR NO.1 CYLINDER,
°)
Ignition timing of No.1 cylinder is commanded by ECM.
The actual ignition timing should be checked by using
the timing light.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage
inputted from main relay to ECM.
FUEL PUMP (ON/OFF)
ON is displayed when ECM activates the fuel pump via
the fuel pump relay switch.
ELECTRIC LOAD (ON/OFF)
ON: Headlight or small light ON signal inputted.
OFF: Above electric loads all turned OFF.
BRAKE SW (ON/OFF)
This parameter indicates the state of the brake switch.
RADIATOR COOLING FAN (RADIATOR COOLING
FAN CONTROL RELAY, ON/OFF)
ON: Command for radiator cooling fan control relay
operation being output.
OFF: Command for relay operation not being output.
BLOWER FAN (ON/OFF)
This parameter indicates the state of the blower fan
motor switch.
A/C SWITCH (ON/OFF)
ON: Command for A/C operatio n being output from ECM
to HVAC.
OFF: Command for A/C oper ation not being output.
A/C COMP RELAY (A/C COMPRESSOR RELAY, ON/
OFF)
This parameter indicates the state of the A/C switch.
VEHICLE SPEED (km/h, mph)
It is computed based on pulse signals from vehicle
speed sensor.
VVT GAP (TARGET-ACTUAL POSITION, °)
It is calculated using the formula: target valve timing
advance – actual valve timing advance.
TP SENSOR 1 VOLT (THROTTLE POSITION SENSOR
(MAIN) OUTPUT VOLTAGE, V)
The TP sensor (main) reading provides throttle valve
opening information in the form of voltage.

Downloaded from www.Manualslib.com manuals search engine 1A-40 Engine General Information and Diagnosis:
11Check fuel pump for operation
Was fuel pump operating sou nd 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”.
12 Check ignition spark
1) Disconnect injector couplers.
2) Remove spark plugs and connect them to high-tension
cords or ignition coil assemblies.
3) Ground spark plugs.
4) Crank engine and check if each spark plug sparks.
Is it in good condition? Go to Step 13. Go to “Ignition Spark
Test in Section 1H”.
13 Check fuel injector for operation
1) Install spark plugs and connect injector connectors.
2) Using sound scope (1), check operating sound of each
injector (2) when cranking engine.
Was injector operating sound heard from all injectors? Go to “Engine Symptom
Diagnosis”.
Go to “Fuel Injector
Circuit Check”.
Step Action Yes No
I3RM0A110015-01

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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 in Section 1B”
High idle speed Condition “Improper engine idling or engine
fails to idle”
Poor performance of ECT sensor or
MAF sensor “ECT Sensor Inspection in Section 1C” or
“MAF and 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 “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 brakes Condition “Dragging brakes” in “Brakes
Symptom Diagnosis in Section 4A”
Slipping clutch Condition “Slipping clutch” in “Clutch System
Symptom Diagnosis in Section 5C”
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 “Oil Control Valve Inspection in Section 1D”
Excessive engine oil
consumption – Oil
leakage Blown cylinder head gasket
“Cylinder Head Inspection in Section 1D”
Leaky camshaft oil seals “Camshaft, Tappet and Shim Inspection in
Section 1D”
Excessive engine oil
consumption – Oil
entering combustion
chamber Sticky 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”
Condition Possible cause Correction / Reference Item

Downloaded from www.Manualslib.com manuals search engine 1A-44 Engine General Information and Diagnosis:
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
“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 in Section 1B”
Poor performance of ECT sensor or
MAF sensor “ECT Sensor Inspection in Section 1C” or
“MAF and 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 “APP Sensor Assembly Inspection in Section
1C”
Faulty fuel injector “Fuel Injector Circuit Check”
Faulty ECM
Engine overheating Condition “Engine overheating”
Low compression “Compression Check in Section 1D”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection 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 in Section 1B”
Poor performance of MAF sensor “MAF and IAT Sensor Inspection in Section
1C”
Faulty fuel injector “Fuel Injector Circuit Check”
Faulty electric throttle body assembly “Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly “APP Sensor Assembly Inspection in Section
1C”
Faulty ECM
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 overheating Condition “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 in Section 1B”
Poor performance of knock sensor, ECT
sensor or MAF sensor “DTC P0327 / P0328: Knock Sensor 1 Circuit
Low / High”, “ECT Sensor Inspection in
Section 1C” or “MAF and 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 In
spection in Section
1D”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Condition Possible cause Correction / Reference Item

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-45
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 1 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 overheating Condition “Engine overheating”
Malfunctioning EGR valve “EGR Valve Inspection in Section 1B”
Poor performance of ECT sensor or
MAF sensor “ECT Sensor Inspection in Section 1C” or
“MAF and 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 “APP Sensor Assembly Inspection in Section
1C”
Faulty fuel injector(s) “Fuel Injector Circuit Check”
Faulty ECM
Dragging brakes Condition “Dragging brakes” in “Brakes
Symptom Diagnosis in Section 4A”
Slipping clutch Condition “Slipping clutch” in “Clutch System
Symptom Diagnosis in Section 5C”
Low compression “Compression Check in Section 1D”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Improper engine idling or
engine fails to idle 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”
Fuel pressure out of specification “Fuel Pressure Check”
Leaky manifold, throttle body, or cylinder
head gasket
Malfunctioning EGR valve “EGR Valve Inspection in Section 1B”
Faulty evaporative emission control
system “EVAP Canister Purge Inspection in Section
1B”
Faulty EGR system “EGR System Inspection in Section 1B”
Faulty fuel injector(s) “Fuel Injector Circuit Check”
Poor performance of ECT sensor or
MAF sensor “ECT Sensor Inspection in Section 1C” or
“MAF and 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 “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 overheating Condition “Engine overheating”
Low compression “Compression Check in Section 1D”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Condition Possible cause Correction / Reference Item

Downloaded from www.Manualslib.com manuals search engine 1A-46 Engine General Information and Diagnosis:
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 converter Check for absence of f
iller 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 (Faulty TP sensor,
Poor performance of ECT sensor or
MAF sensor) “Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”, “ECT Sensor
Inspection in Section 1C” or “MAF and 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 “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 Element Inspection and Cleaning
in Section 1D”
Vacuum leaks “Engine Vacuum Check in Section 1D”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Excessive nitrogen
oxides (NOx) emission Improper ignition timing
“Ignition Timing Inspection in Section 1H”
Lead contamination of catalytic
converter Check for absence of f
iller neck restrictor.
Faulty EGR system “EGR System Inspection in Section 1B”
Fuel pressure out of specification “Fuel Pressure Check”
Closed loop system (A/F feedback
compensation) fails (Faulty TP sensor,
Poor performance of ECT sensor or
MAF sensor) “Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”, “ECT Sensor
Inspection in Section 1C” or “MAF and 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 “APP Sensor Assembly Inspection in Section
1C”
Faulty injector(s) “Fuel Injector Circuit Check”
Faulty ECM
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Condition Possible cause Correction / Reference Item

Downloaded from www.Manualslib.com manuals search engine 1A-98 Engine General Information and Diagnosis:
DTC P0171 / P0172: Fuel System Too Lean / RichS7RS0B1104036
DTC Detecting Condition and Trouble Area
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 ar e 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: 40 °C (104 °F) to 120 °C (248 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

3 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Measure resistance between “BRN” wire terminal of HO2S-2 connector and “C37-11” terminal of ECM
connector.
Is resistance less than 5
Ω? Go to Step 4. “BRN” wire is high
resistance circuit or
open circuit. Poor “C37-
11” terminal connection.
If they are OK,
substitute a known-
good ECM and recheck.
4 HO2S-2 signal circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure voltage between “BRN” wire terminal of HO2S- 2 connector and vehicle body ground.
Is voltage 0 V? Go to Step 5. “BRN” wire is shorted to
other circuit.
5 HO2S-2 heater circuit check
1) Check HO2S-2 heater circuit referring to “DTC P0037 /
P0038: HO2S Heater Control Circuit Low / High
(Sensor-2)”.
Is circuit in good condition? Go to Step 6. Repair HO2S-2 circuit. If
circuit is OK, substitute
a known-good ECM and
recheck.
6 HO2S-2 check
1) Check HO2S-2 referring to “HO2S-1 and HO2S-2
Heater On-Vehicle Inspection in Section 1C”.
Is it in good condition? Substitute a known-
good ECM and recheck.
Replace HO2S-2.
Step Action Yes No
DTC detecting condition
Trouble area
DTC P0171:
Total fuel trim is higher than 35% or short term fuel trim is higher
than 20% for more than 1 min. continuously.
(2 driving cycle detection logic)
DTC P0172:
Total fuel trim is lower than –35% or short term fuel trim is lower
than –20% for more than 1 min. continuously.
(2 driving cycle detection logic) • Vacuum leakage
• Exhaust gas leakage
• Fuel pressure out of specification
• Fuel injector malfunction
• Heated oxygen sensor-1 malfunction
• MAF sensor malfunction
• ECT sensor malfunction

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1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and print Freeze Frame Data or write them down using scan tool.
3) Clear DTC using scan tool.
4) Start engine and warm up to normal operating temperature.
5) Operate vehicle with condition as noted freeze frame data for 5 min.
6) Stop vehicle and check DTC and pending DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

Step Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Is there DTC(s) other than fuel system (DTC P0171 /
P0172)? Go to applicable DTC
diag. flow.Go to Step 3.
3 Intake system and exhaust system for leakage check
Are intake system and exhaust system in good condition? Go to Step 4.
Repair or replace
defective part.
4 Fuel pressure check
1) Check fuel pressure referring to “Fuel Pressure Check”.
Is check result satisfactory? Go to Step 5.
Repair or replace
defective part.
5 Fuel injectors and its circuit check
1) Check fuel injectors referring to “Fuel Injector Inspection
in Section 1G”.
Is check result satisfactory? Go to Step 6.
Faulty injector(s) or its
circuit.
6 Visual inspection
1) Check MAF sensor and air intake system.
• Objects which block measur ing duct and resistor of
MAF sensor.
• Other air flow which does not pass MAF sensor.
Are they in good condition? Go to Step 7.
Repair or replace
defective part.
7 MAF sensor for performance check
1) With ignition switch turn ed OFF, install scan tool.
2) Start engine and warm up to normal operating temperature.
3) Check MAF value using scan tool (Refer to “Scan Tool Data” for normal value.).
Is each value within specified range? Go to Step 8.
Go to “DTC P0101:
Mass or Volume Air
Flow Circuit Range /
Performance”.
8 ECT sensor for performance check
1) Check ECT sensor referring to Step 3 and 4 of “DTC
P0118: Engine Coolant Temperature Circuit High”.
Is check result satisfactory? Go to Step 9.
Faulty ECT sensor or its
circuit.

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DTC P0300 / P0301 / P0302 / P0303 / P0304: Random / Multiple Cylinder Misfire Detected / Cylinder 1
/ Cylinder 2 / Cylinder 3 / Cylinder 4 Misfire Detected
S7RS0B1104039
System Description
ECM measures the angle of the crankshaft based on the pulse signal from the CKP sensor and CMP sensor for each
cylinder. If it detects a large change in the angle speed of the crankshaft, it concludes occurrence of a misfire. When
the number of misfire is counted by ECM beyond the DTC de tecting condition, it determines the cylinder where the
misfire occurred and output it as DTC.
DTC Detecting Condition and Trouble Area
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 ar e 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 temp.: –10 °C, 14 °F or higher
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and print Freeze Frame Data or write them down using scan tool.
3) Clear DTC using scan tool.
4) Drive vehicle under freeze frame data condition as noted for 1 min. or more.
5) Stop vehicle and check DTC and pending DTC. 11
Electric throttle body check
1) Check TP sensor referring to “Throttle Position Sensor
Performance Check” under “Electric Throttle Body
Assembly On-Vehicle Inspection in Section 1C”.
Is output voltage within specified value? Substitute a known-
good ECM and recheck.
Replace electric throttle
body.
Step Action Yes No
DTC detecting condition
Trouble area
DTC P0300:
• Misfire, which causes catalyst to overheat during 200 engine revolutions, is detected at 2 or more cylinders. (MIL flashes as lo ng as this misfire occurs continuously.)
or
• Misfire, which affects exhaust emission adv ersely during 1000 engine revolution, is
detected at 2 or more cylinders. (2 driving cycle detection logic) • Ignition system
• Fuel injector and its circuit
• Fuel pressure
• EGR system
• Abnormal air drawn in
• Engine compression
• Valve lash adjuster
• Valve timing
• Fuel shortage
• Exhaust system
• Fuel of poor quality
DTC P0301, P0302, P0303, P0304:
• Misfire, which causes catalyst to overheat during 200 engine revolutions, is detected
at 1 cylinder. (MIL flashes as long as this misfire occurs continuously.)
or
• Misfire, which affects exhaust emission adv ersely during 1000 engine revolution, is
detected at 1 cylinder. (2 driving cycle detection logic)