Engine General Information and Diagnosis SUZUKI SWIFT 2007 2.G Service Owners Manual
[x] Cancel search | Manufacturer: SUZUKI, Model Year: 2007, Model line: SWIFT, Model: SUZUKI SWIFT 2007 2.GPages: 1496, PDF Size: 34.44 MB
Page 136 of 1496

Downloaded from www.Manualslib.com manuals search engine 1A-86 Engine General Information and Diagnosis: 
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 TP sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned 
OFF.
2) Turn ON ignition switch, check “TP Sensor 1 Volt”  displayed on scan tool when accelerator pedal is idle 
position and fully depressed.
Is displayed TP sensor value as described voltage in “Scan 
To o l  D a t a ” ? Intermittent trouble.
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
Go to Step 3.
3 ECM voltage check
1) Disconnect connector from electric throttle body with 
ignition switch turned OFF.
2) Check for proper connection to electric throttle body at  “RED”, “GRN” and “BLK” wire terminals.
3) If OK, measure voltage between “RED” wire terminal of  electric throttle body connector and engine ground with 
ignition switch turned ON.
Is voltage 4 – 6 V? Go to Step 5.
Go to Step 4.
4 Wire harness check
1) Disconnect connectors from ECM with ignition switch 
turned OFF.
2) Check for proper connection of ECM connector at “C37- 43” terminal.
3) Measured voltage between “C37-43” terminal of ECM  connector and engine ground with ignition switch turned 
ON.
Is voltage 0 V? Substitute a known-
good ECM and recheck.
“RED” wire is shorted to 
power circuit.
5 Wire harness check
1) Measure voltage between “GRN” wire terminal of electric 
throttle body connector and engine ground with ignition 
switch turned ON.
Is voltage 4 – 6 V? Go to Step 9.
Go to Step 6.
"GRN"
"RED"
"WHT"
"BLK"
"LT GRN/BLK"
"LT GRN/RED"
I4RS0B110022-02  
Page 137 of 1496

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6Wire harness check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors 
connected.
3) Check for proper connection of ECM connector at “C37- 43” and “C37-54” terminals.
4) If OK, measure voltage between “C37-54” terminal of  ECM connector and engine ground with ignition switch 
turned ON.
Is voltage 4 -6 V? “GRN” wire is open or 
high resistance circuit.
Go to Step 7.
7 Wire harness check
1) Disconnect connectors from ECM with ignition switch 
turned OFF.
2) Measure resistance between “GRN” and “RED” wire  terminals of electric th rottle body connector.
Is resistance infinity? Go  to Step 8. “GRN” wire is shorted to 
“RED” wire.
8 Wire harness check
1) Turn ON ignition switch.
2) Measure voltage between “C37-54” terminal of ECM 
connector and engine ground.
Is voltage 0 V? Substitute a known-
good ECM and recheck.
“GRN” wire is shorted to 
power circuit.
9 Ground circuit check
1) Turn OFF ignition switch.
2) Measure resistance between “BLK” wire terminal of 
electric throttle body connector and engine ground.
Is resistance below 5 
Ω? Go to Step 11. Go to Step 10.
10 Ground circuit check
1) Remove ECM from its br acket with ECM connectors 
connected.
2) Check for proper connection of ECM connector at “C37- 42” terminal.
3) Measure resistance between “C37-42” terminal of ECM  connector and engine ground with ignition switch turned 
OFF.
Is resistance below 5 
Ω? “BLK” wire is open or 
high resistance circuit.
Faulty ECM ground 
circuit. If circuit is OK, 
substitute a known-
good ECM and recheck.
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  
Page 138 of 1496

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DTC P0131 / P0132: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-1)S7RS0B1104031
Wiring Diagram
DTC Detecting Condition and Trouble Area
E23C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
BLK/WHT
WHT
11
GRN
3 9
E23-29  
WHT
YEL
BLK/WHT
BLKC37-46  
C37-10  
C37-57  
6
7
10
BLK
BLUWHT
BLK/RED
4
5
8
12
1
I6RS0C110006-03
1. Main fuse box
4. Junction block assembly 7. Heater 10. To HO2S-2
2. Shield wire 5. “IG COIL” fuse8. To HO2S-2 heater 11. Individual circuit fuse box No.1
3. Ignition switch 6. HO2S-19. ECM 12. “IG ACC” fuse
DTC detecting condition Trouble area
DTC P0131:
Maximum HO2S voltage is less than 0.6 V
(*2 driving cycle detection logic, monitoring once per driving cycle)
DTC P0132:
Minimum HO2S voltage is 0.3 V or more
(*2 driving cycle detection logic, monitoring once per driving cycle) • HO2S-1 circuit
•HO2S-1 
• Fuel system
•ECM
• Fuel shortage
• Exhaust system
• Air intake system  
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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: 70  °C (158  °F) to 150  °C (302  °F)
• 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 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. (Throt tle 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) 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 HO2S-1? Go to applicable DTC 
diag. flow.Go to Step 3.
3 HO2S-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 continuous ly 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.  
Page 140 of 1496

Downloaded from www.Manualslib.com manuals search engine 1A-90 Engine General Information and Diagnosis: 
4HO2S-1 ground check
1) Disconnect connector from HO 2S-1 with ignition switch 
turned OFF.
2) Check for proper connection to HO2S-1 connector at  “BLK/RED”, “WHT”, “BLK /WHT” and “YEL” wire 
terminals.
3) If connections are OK, m easure resistance between 
“YEL” wire terminal of HO2S-1 connector and engine 
ground.
Is measured resistance less than 5 
Ω? Go to Step 5. “YEL” wire is open or 
high resistance circuit. 
Poor “C37-57” terminal 
connection. Faulty ECM 
ground.
If they are OK, 
substitute a known-
good ECM and recheck.
5 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors 
connected.
3) Measure resistance between “WHT” wire terminal of  HO2S-1 connector and “C37-10” terminal of ECM 
connector.
Is resistance less than 5 
Ω? Go to Step 6. “WHT” wire is high 
resistance circuit or 
open circuit. Poor “C37-
10” terminal connection. 
Faulty ECM ground. If 
they are OK, substitute 
a known-good ECM and 
recheck.
6 Wire 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.
7 HO2S-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.
8 HO2S-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.
9 Exhaust 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.
10 Air intake system check
1) Check air intake system for clog or leak.
Is it OK? Check HO2S-1 referring 
to “HO2S-1 and HO2S-
2 Heater On-Vehicle 
Inspection in Section 
1C”.
If it is in good condition, 
substitute a known-
good ECM and recheck.Repair or replace air 
intake system.
Step Action Yes No  
Page 141 of 1496

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DTC P0133: O2 Sensor (HO2S) Circuit Slow Response (Sensor-1)S7RS0B1104032
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: 70  °C (158  °F) to 150  °C (302  °F)
• 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 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. (Throt tle 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) Check if DTC and pending DTC exist by  using scan tool. If not, check if oxygen sensor monitoring test has been 
completed by using scan tool. If not in both of above c hecks (i.e., no DTC and pending DTC and oxygen sensor 
monitoring test not completed), check vehicle cond ition (environmental) and repeat Step 3) through 6).
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.
 
DTC detecting condition Trouble area
Response time (time to change from lean to rich or from rich to lean) of HO2S-1 output 
voltage is about 1 sec. at minimum or aver age time of 1 cycle is 5 sec. at minimum.
(*2 driving cycle detection logic, monitoring once per driving cycle) Heated oxygen sensor-1
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 HO2S-1 (DTC P0133)? Go to applicable DTC 
diag. flow.Replace HO2S-1.  
Page 142 of 1496

Downloaded from www.Manualslib.com manuals search engine 1A-92 Engine General Information and Diagnosis: 
DTC P0134: O2 Sensor (HO2S) Circuit No Activity Detected (Sensor-1)S7RS0B1104033
Wiring Diagram
Refer to “DTC P0131 / P0132: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-1)”
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: 70  °C (158  °F) to 150  °C (302 ° F)
• 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 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. (Throt tle 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) Check if DTC and pending DTC exist by  using scan tool. If not, check if oxygen sensor monitoring test has been 
completed by using scan tool. If not in both of above c hecks (i.e., no DTC and pending DTC and oxygen sensor 
monitoring test not completed), check vehicle cond ition (environmental) and repeat Step 3) through 6).
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.
 
DTC detecting condition Trouble area
HO2S voltage is higher than 0.6 V for more than 1 min 
continuously after warming up engine or HO2S voltage is lower 
than 0.3 V for more than 1 min continuously after warming up 
engine.
(2 driving cycle detection logic) •HO2S-1
• HO2S-1 circuit
• Exhaust gas leakage
•ECM
• Air intake system
Step
Action YesNo
1 Was “Engine and Emission Control System Check” 
performed? Go to Step 2.
Go to “Engine and 
Emission Control 
System Check”.  
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2HO2S-1 output voltage 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 continuous ly to enrich A/F mixture and 
take foot off from pedal to enlean it) and check HO2S 
output voltages displayed on scan tool.
Is over 0.6 V and below 0.3 V indicated? Intermittent trouble. 
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”. If check result is 
OK, go to Step 3.
Go to Step 3.
3 HO2S-1 ground check
1) Disconnect connector from HO 2S-1 with ignition switch 
turned OFF.
2) Check for proper connection to HO2S-1 at “BLK/RED”,  “WHT”, “BLK/WHT” and “YEL” wire terminals.
3) If wire and connection are OK, measure resistance  between “YEL” wire terminal of HO2S-1 connector and 
engine ground.
Is resistance less than 5 
Ω? Go to Step 4. “YEL” wire is open or 
high resistance circuit. 
Poor “C37-57” terminal 
connection. Faulty ECM 
ground.
If they are OK, 
substitute a known-
good ECM and recheck.
4 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors 
connected.
3) Measure resistance between “WHT” wire terminal of  HO2S-1 connector and “C37-10” terminal of ECM 
connector.
Is resistance less than 5 
Ω? Go to Step 5. “WHT” wire is high 
resistance circuit or 
open circuit. Poor “C37-
10” terminal connection 
of ECM connector.
Faulty ECM ground. If 
they are OK, substitute 
a known-good ECM and 
recheck.
5 Wire circuit check
1) Disconnect connectors from ECM with ignition switch 
turned OFF.
2) Measure resistance between “WHT” wire terminal of  HO2S-1 connector and vehicle body ground.
Is resistance infinity? Go to Step 6. “WHT” wire is shorted to 
ground circuit.
6 HO2S-1 heater circuit check
1) Check HO2S-1 heater circuit referring to “DTC P0031 / 
P0032: HO2S Heater Control Circuit Low / High 
(Sensor-1)”.
Is it in good condition? Go to Step 7. Repair HO2S-1 circuit.
7 Exhaust 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 8.Repair leakage of 
exhaust system.
8 Air intake system check
1) Check air intake system for clog or leak.
Is it OK? Check HO2S-1 referring 
to “HO2S-1 and HO2S-
2 Heater On-Vehicle 
Inspection in Section 
1C”.
If it is in good condition, 
substitute a known-
good ECM and recheck.Repair or replace air 
intake system.
Step Action Yes No  
Page 144 of 1496

Downloaded from www.Manualslib.com manuals search engine 1A-94 Engine General Information and Diagnosis: 
DTC P0137 / P0138: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-2)S7RS0B1104034
Wiring Diagram
DTC Detecting Condition and Trouble Area
E23C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
BLK/WHT
WHT
11
GRN
3 9
E23-29  
BRN
YEL
BLK/WHT
BLKC37-47  
C37-11  
C37-57  
6
2
7
10
BLK
BLUWHT
RED/BLU
1
4
5
8
12
5V  
I6RS0C110007-01
1. Main fuse box 4. Junction block assembly 7. Heater 10. To HO2S-1
2. Shield wire 5. “IG COIL” fuse8. To HO2S-1 heater 11. Individual circuit fuse box No.1
3. Ignition switch 6. HO2S-29. ECM 12. “IG ACC” fuse
DTC detecting condition Trouble area
DTC P0137:
HO2S-2 voltage is lower th an 0.4 V while engine is idling after driving with 
high engine load (high speed) for specified time. And HO2S-2 max. voltage 
minus HO2S-2 min. voltage is less than 0.1 V for 40 sec continuously.
(2 driving cycle detection logic)
DTC P0138:
HO2S-2 voltage is higher than 0.95  V while engine is idling after driving 
with high engine load (high speed) for specified time. And HO2S-2 max. 
voltage minus HO2S-2 min. voltage is less than 0.1 V for 40 sec 
continuously.
(2 driving cycle detection logic) •HO2S-2
• HO2S-2 circuit
• Fuel system
•ECM
• Fuel shortage
• Exhaust system
• Air intake system  
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Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis:  1A-95
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: 70  °C (158  °F) to 150  °C (302 °F)
• 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 clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature.
4) Increase vehicle speed to 70 – 80 km/h (43 – 50 mile/h) at 5th gear or D range.
5) Release accelerator pedal and with engine brake applied, ke ep vehicle coasting (with fuel cut for 4 sec. or more), 
then stop vehicle and run engine at idle speed for 60 sec. or more.
6) Repeat Step 4).
7) Keep above vehicle speed for 8 min. or more. (Throt tle valve opening is kept constant in this step.)
8) Repeat Step 5).
9) 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) 
and HO2S-2 (DTC P0140)? Go to applicable DTC 
diag. flow.Go to Step 3.
3 HO2S-2 and its circuit 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 continuous ly to enrich A/F mixture and 
take foot off from pedal to enlean it).
Does HO2S-2 output voltage indicate deflection between 
over 0.35 V and below 0.25 V? Go to “DTC P0171 / 
P0172: Fuel System 
Too Lean / Rich”.
Go to Step 4.