sensor NISSAN 350Z 2007 Z33 Engine Control Manual PDF

EC-120
TROUBLE DIAGNOSIS
Revision: 2006 November2007 350Z
*: This item is the same as that of 1st trip freeze frame data.
DATA MONITOR MODE
Monitored Item
×: Applicable ENGINE SPEED
[rpm]

The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED
[km/h] or [mph]

The vehicle speed at the moment a malfunction is detected is displayed.
ABSOL TH-P/S [%]

The throttle valve operating angle at the moment a malfunction is detected is displayed.
B/FUEL SCHDL
[msec]

The base fuel schedule at the moment a malfunction is detected is displayed.
INT/A TEMP SE
[°C] or [°F]

The intake air temperature at the moment a malfunction is detected is displayed. Freeze frame data
item*Description
Monitored item [Unit] Description Remarks
ENG SPEED [rpm]

Indicates the engine speed computed from the signals
of the crankshaft position sensor (POS) and camshaft
position sensor (PHASE).
Accuracy becomes poor if engine speed drops
below the idle rpm.

If the signal is interrupted while the engine is
running, an abnormal value may be indicated.
MAS A/F SE-B1 [V]

The signal voltage of the mass air flow sensor is dis-
played.

When the engine is stopped, a certain value is
indicated.

When engine is running specification range is
indicated in “SPEC”. MAS A/F SE-B2 [V]
B/FUEL SCHDL [msec]

“Base fuel schedule” indicates the fuel injection pulse
width programmed into ECM, prior to any learned on
board correction.
When engine is running specification range is
indicated in “SPEC”.
A/F ALPHA-B1 [%]

The mean value of the air-fuel ratio feedback correc-
tion factor per cycle is indicated.

When the engine is stopped, a certain value is
indicated.

This data also includes the data for the air-fuel
ratio learning control.

When engine is running specification range is
indicated in “SPEC”. A/F ALPHA-B2 [%]
COOLAN TEMP/S [°C]
or [°F]

The engine coolant temperature (determined by the
signal voltage of the engine coolant temperature sen-
sor) is displayed.
When the engine coolant temperature sensor
is open or short-circuited, ECM enters fail-safe
mode. The engine coolant temperature deter-
mined by the ECM is displayed.
A/F SEN1 (B1) [V]

The A/F signal computed from the input signal of the
A/F sensor 1 is displayed.
A/F SEN1 (B2) [V]
HO2S2 (B1) [V]

The signal voltage of the heated oxygen sensor 2 is
displayed.
HO2S2 (B2) [V]
HO2S2 MNTR(B1)
[RICH/LEAN]

Display of heated oxygen sensor 2 signal:
RICH: Means the amount of oxygen after three way
catalyst is relatively small.
LEAN: Means the amount of oxygen after three way
catalyst is relatively large.

When the engine is stopped, a certain value is
indicated.
HO2S2 MNTR(B2)
[RICH/LEAN]
VHCL SPEED SE [km/
h] or [mph]

The vehicle speed computed from the vehicle speed
signal sent from combination meter is displayed.
BATTERY VOLT [V]

The power supply voltage of ECM is displayed.
ACCEL SEN 1 [V]

The accelerator pedal position sensor signal voltage is
displayed.
ACCEL SEN 2 signal is converted by ECM
internally. Thus, it differs from ECM terminal
voltage signal. ACCEL SEN 2 [V]

TROUBLE DIAGNOSIS
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TP SEN 1-B1 [V]
The throttle position sensor signal voltage is dis-
played.
THRTL SEN 2-B1 signal is converted by ECM
internally. Thus, it differs from ECM terminal
voltage signal. TP SEN 2-B1 [V]
FUEL T/TMP SE [°C]
or [°F]

The fuel temperature (determined by the signal volt-
age of the fuel tank temperature sensor) is displayed.
INT/A TEMP SE [°C] or
[°F]

The intake air temperature (determined by the signal
voltage of the intake air temperature sensor) is indi-
cated.
EVAP SYS PRES [V]

The signal voltage of EVAP control system pressure
sensor is displayed.
FUEL LEVEL SE [V]

The signal voltage of the fuel level sensor is displayed.
START SIGNAL [ON/
OFF]

Indicates start signal status [ON/OFF] computed by
the ECM according to the signals of engine speed and
battery voltage.
After starting the engine, [OFF] is displayed
regardless of the starter signal.
CLSD THL POS [ON/
OFF]

Indicates idle position [ON/OFF] computed by ECM
according to the accelerator pedal position sensor sig-
nal.
AIR COND SIG [ON/
OFF]

Indicates [ON/OFF] condition of the air conditioner
switch as determined by the air conditioner signal.
P/N POSI SW
[ON/OFF]

Indicates [ON/OFF] condition from the park/neutral
position (PNP) switch signal.
PW/ST SIGNAL [ON/
OFF]

[ON/OFF] condition of the power steering system
(determined by the signal voltage of the power steer-
ing pressure sensor) is indicated.
LOAD SIGNAL [ON/
OFF]

Indicates [ON/OFF] condition from the electrical load
signal.
ON: Rear window defogger switch is ON and/or light-
ing switch is in 2nd position.
OFF: Both rear window defogger switch and lighting
switch are OFF.
IGNITION SW
[ON/OFF]

Indicates [ON/OFF] condition from ignition switch sig-
nal.
HEATER FAN SW
[ON/OFF]

Indicates [ON/OFF] condition from the heater fan
switch signal.
BRAKE SW
[ON/OFF]

Indicates [ON/OFF] condition from the stop lamp
switch signal.
INJ PULSE-B1 [msec]

Indicates the actual fuel injection pulse width compen-
sated by ECM according to the input signals.
When the engine is stopped, a certain com-
puted value is indicated.
INJ PULSE-B2 [msec]
IGN TIMING [BTDC]

Indicates the ignition timing computed by ECM
according to the input signals.
When the engine is stopped, a certain value is
indicated.
CAL/LD VALUE [%]

“Calculated load value” indicates the value of the cur-
rent air flow divided by peak air flow.
MASS AIRFLOW [g·m/
s]

Indicates the mass air flow computed by ECM accord-
ing to the signal voltage of the mass air flow sensor.
PURG VOL C/V [%]

Indicates the EVAP canister purge volume control
solenoid valve control value computed by the ECM
according to the input signals.

The opening becomes larger as the value increases.
INT/V TIM(B1) [°CA]

Indicates [°CA] of intake camshaft advanced angle.
INT/V TIM(B2) [°CA]
EXH/V TIM B1 [°CA]

Indicates [°CA] of exhaust camshaft retarded angle.
EXH/V TIM B2 [°CA] Monitored item [Unit] Description Remarks

EC-122
TROUBLE DIAGNOSIS
Revision: 2006 November2007 350Z
INT/V SOL(B1) [%]
The control value of the intake valve timing control
solenoid valve (determined by ECM according to the
input signals) is indicated.

The advance angle becomes larger as the value
increases. INT/V SOL(B2) [%]
EX VTC DTY B1 [%]

The control value of the exhaust valve timing control
magnet retarder (determined by ECM according to the
input signals) is indicated.

The retard angle becomes larger as the value
increases. EX VTC DTY B2 [%]
TP SEN 1-B2 [V]

The throttle position sensor signal voltage is dis-
played.
THRTL SEN 2-B2 signal is converted by ECM
internally. Thus, it differs from ECM terminal
voltage signal. TP SEN 2-B2 [V]
AIR COND RLY [ON/
OFF]

The air conditioner relay control condition (determined
by ECM according to the input signals) is indicated.
FUEL PUMP RLY [ON/
OFF]

Indicates the fuel pump relay control condition deter-
mined by ECM according to the input signals.
VENT CONT/V [ON/
OFF]

The control condition of the EVAP canister vent control
valve (determined by ECM according to the input sig-
nals) is indicated.
ON: Closed
OFF: Open
THRTL RELAY [ON/
OFF]

Indicates the throttle control motor relay control condi-
tion determined by the ECM according to the input sig-
nals.
COOLING FAN
[HI/LOW/OFF]

The control condition of the cooling fan (determined by
ECM according to the input signals) is indicated.
HI: High speed operation
LOW: Low speed operation
OFF: Stop
HO2S2 HTR (B1) [ON/
OFF]

Indicates [ON/OFF] condition of heated oxygen sensor
2 heater determined by ECM according to the input
signals. HO2S2 HTR (B2) [ON/
OFF]
I/P PULLY SPD
[rpm]

Indicates the engine speed computed from the turbine
revolution sensor signal.
VEHICLE SPEED
[km/h] or [mph]

Indicates the vehicle speed computed from the revolu-
tion sensor signal.
IDL A/V LEARN [YET/
CMPLT]

Display the condition of Idle Air Volume Learning
YET: Idle Air Volume Learning has not been performed
yet.
CMPLT: Idle Air Volume Learning has already been
performed successfully.
TRVL AFTER MIL [km]
or [mile]

Distance traveled while MIL is activated.
ENG OIL TEMP [°C] or
[°F]

The engine oil temperature (determined by the signal
voltage of the engine oil temperature sensor) is dis-
played.
A/F S1 HTR(B1) [%]

Indicates A/F sensor 1 heater control value computed
by ECM according to the input signals.

The current flow to the heater becomes larger as the
value increases. A/F S1 HTR(B2) [%]
AC PRESS SEN [V]

The signal voltage from the refrigerant pressure sen-
sor is displayed. Monitored item [Unit] Description Remarks

TROUBLE DIAGNOSIS
EC-123
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NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.VHCL SPEED SE [km/
h] or [mph]

The vehicle speed computed from the vehicle speed
signal sent from TCM is displayed.
SET VHCL SPD
[km/h] or [mph]

The preset vehicle speed is displayed.
MAIN SW
[ON/OFF]

Indicates [ON/OFF] condition from MAIN switch sig-
nal.
CANCEL SW
[ON/OFF]

Indicates [ON/OFF] condition from CANCEL switch
signal.
RESUME/ACC SW
[ON/OFF]

Indicates [ON/OFF] condition from RESUME/ACCEL-
ERATE switch signal.
SET SW
[ON/OFF]

Indicates [ON/OFF] condition from SET/COAST
switch signal.
BRAKE SW1
[ON/OFF]

Indicates [ON/OFF] condition from ASCD brake switch
signal and ASCD clutch switch signal (M/T)
BRAKE SW2
[ON/OFF]

Indicates [ON/OFF] condition of stop lamp switch sig-
nal.
VHCL SPD CUT
[NON/CUT]

Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the ASCD set
speed.
CUT: Vehicle speed decreased to excessively low
compared with the ASCD set speed, and ASCD oper-
ation is cut off.
LO SPEED CUT
[NON/CUT]

Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the ASCD set
speed.
CUT: Vehicle speed decreased to excessively low, and
ASCD operation is cut off.
AT OD MONITOR
[ON/OFF]

Indicates [ON/OFF] condition of A/T O/D according to
the input signal from the TCM.
For M/T models always “OFF” is displayed.
AT OD CANCEL
[ON/OFF]

Indicates [ON/OFF] condition of A/T O/D cancel
request signal.
For M/T models always “OFF” is displayed.
CRUISE LAMP
[ON/OFF]

Indicates [ON/OFF] condition of CRUISE lamp deter-
mined by the ECM according to the input signals.
SET LAMP
[ON/OFF]

Indicates [ON/OFF] condition of SET lamp determined
by the ECM according to the input signals.
EXH V/T LEARN [YET/
CMPLT]

Display the condition of Exhaust Valve Timing Control
Learning
YET: Exhaust Valve Timing Control Learning has not
been performed yet.
CMPLT: Exhaust Valve Timing Control Learning has
already been performed successfully.
A/F ADJ-B1

Indicates the correction of factor stored in ECM. The
factor is calculated from the difference between the
target air-fuel ratio stored in ECM and the air-fuel ratio
calculated from A/F sensor 1 signal. A/F ADJ-B2
Voltage [V]

Voltage, frequency, duty cycle or pulse width mea-
sured by the probe.

Only “#” is displayed if item is unable to be
measured.

Figures with “#”s are temporary ones. They
are the same figures as an actual piece of data
which was just previously measured. Frequency [msec], [Hz]
or [%]
DUTY-HI
DUTY-LOW
PLS WIDTH-HI
PLS WIDTH-LOWMonitored item [Unit] Description Remarks

EC-124
TROUBLE DIAGNOSIS
Revision: 2006 November2007 350Z
ACTIVE TEST MODE
Test Item
*: Leaving cooling fan “OFF” with CONSULT-III while engine is running may cause the engine to overheat.TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION

Engine: Return to the original
trouble condition

Change the amount of fuel injec-
tion using CONSULT-III.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Fuel injector

Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING

Engine: Return to the original
trouble condition

Timing light: Set

Retard the ignition timing using
CONSULT-III.If trouble symptom disappears, see
CHECK ITEM.

Perform Idle Air Volume Learning.
POWER BAL-
ANCE

Engine: After warming up, idle
the engine.

A/C switch OFF

Shift lever: P or N (A/T), Neutral
(M/T)

Cut off each fuel injector signal
one at a time using CONSULT-III.Engine runs rough or dies.

Harness and connectors

Compression

Fuel injector

Power transistor

Spark plug

Ignition coil
COOLING FAN
*

Ignition switch: ON

Turn the cooling fan “HI”, “LOW”
and “OFF” using CONSULT-III.Cooling fan moves and stops.

Harness and connectors

Cooling fan motor

IPDM E/R
ENG COOLANT
TEMP

Engine: Return to the original
trouble condition

Change the engine coolant tem-
perature using CONSULT-III.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Engine coolant temperature sen-
sor

Fuel injector
FUEL PUMP
RELAY

Ignition switch: ON
(Engine stopped)

Turn the fuel pump relay “ON”
and “OFF” using CONSULT-III
and listen to operating sound.Fuel pump relay makes the operat-
ing sound.
Harness and connectors

Fuel pump relay
PURG VOL
CONT/V

Engine: After warming up, run
engine at 1,500 rpm.

Change the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT-III.Engine speed changes according to
the opening percent.
Harness and connectors

Solenoid valve
FUEL/T TEMP
SEN

Change the fuel tank temperature using CONSULT-III.
VENT CON-
TROL/V

Ignition switch: ON
(Engine stopped)

Turn solenoid valve “ON” and
“OFF” with the CONSULT-III and
listen to operating sound.Solenoid valve makes an operating
sound.
Harness and connectors

Solenoid valve
INT V/T ASSIGN
ANGLE

Engine: Return to the original
trouble condition

Change intake valve timing using
CONSULT-III.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Intake valve timing control sole-
noid valve
EXH V/T ASSIGN
ANGLE

Engine: Return to the original
trouble condition

Change exhaust valve timing
using CONSULT-III.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Exhaust valve timing control mag-
net retarder

TROUBLE DIAGNOSIS
EC-127
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5. Perform each diagnostic mode according to each service proce-
dure.
For further information, see the GST Operation Manual of
the tool maker.
CONSULT-III Reference Value in Data MonitorNBS0003P
Remarks:

Specification data are reference values.

Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
i.e. Adjust ignition timing with a timing light before monitoring IGN TIMING, because the monitor may show the specification data in
spite of the ignition timing not being adjusted to the specification data. This IGN TIMING monitors the data calculated by the ECM
according to the signals input from the camshaft position sensor and other ignition timing related sensors.
SEF416S
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED

Run engine and compare CONSULT-III value with the tachometer indica-
tion.Almost the same speed as the
tachometer indication
MAS A/F SE-B1 See EC-132, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
MAS A/F SE-B2 See EC-132, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
B/FUEL SCHDL See EC-132, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
A/F ALPHA-B1
A/F ALPHA-B2See EC-132, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
COOLAN TEMP/S

Engine: After warming up More than 70°C (158°F)
A/F SEN1 (B1)
A/F SEN1 (B2)

Engine: After warming up Maintaining engine speed at 2,000 rpm Fluctuates around 2.2V
HO2S2 (B1)
HO2S2 (B2)

Revving engine from idle to 3,000 rpm quickly after the following conditions
are met
–Engine: After warming up
–Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no load0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR(B1)
HO2S2 MNTR(B2)

Revving engine from idle to 3,000 rpm quickly after the following conditions
are met
–Engine: After warming up
–Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no loadLEAN ←→ RICH
VHCL SPEED SE

Turn drive wheels and compare CONSULT-III value with the speedometer
indication.Almost the same speed as the
speedometer indication
BATTERY VOLT

Ignition switch: ON (Engine stopped) 11 - 14V
ACCEL SEN 1

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.8V
ACCEL SEN 2*
1
Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.3 - 1.2V
Accelerator pedal: Fully depressed 3.9 - 4.8V
TP SEN 1-B1
TP SEN 2-B1*
1

Ignition switch: ON
(Engine stopped)

Shift lever: D (A/T) or 1st (M/T)
positionAccelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
FUEL T/TMP SE

Ignition switch: ONIndicates fuel tank tempera-
ture
INT/A TEMP SE

Ignition switch: ONIndicates intake air tempera-
ture

TROUBLE DIAGNOSIS
EC-131
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*1: Accelerator pedal position sensor 2 signal and throttle position sensor 2 signal are converted by ECM internally. Thus, they differ
from ECM terminals voltage signal.

EC-132
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Revision: 2006 November2007 350Z
TROUBLE DIAGNOSIS - SPECIFICATION VALUEPFP:00031
DescriptionNBS0003R
The specification (SP) value indicates the tolerance of the value that is displayed in “SPEC” in “DATA MONI-
TOR” mode of CONSULT-III during normal operation of the Engine Control System. When the value in “SPEC”
in “DATA MONITOR” mode is within the SP value, the Engine Control System is confirmed OK. When the
value in “SPEC” in “DATA MONITOR” mode is NOT within the SP value, the Engine Control System may have
one or more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the
MIL.
The SP value will be displayed for the following three items:

B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board cor-
rection)

A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)

MAS A/F SE-B1/B2 (The signal voltage of the mass air flow sensor)
Testing ConditionNBS0003S

Vehicle driven distance: More than 5,000 km (3,107 miles)

Barometric pressure: 98.3 - 104.3 kPa (1.003 - 1.064 kg/cm2 , 14.25 - 15.12 psi)

Atmospheric temperature: 20 - 30°C (68 - 86°F)

Engine coolant temperature: 75 - 95°C (167 - 203°F)

Transmission: Warmed-up
–For A/T models: After the engine is warmed up to normal operating temperature, drive vehicle until “ATF
TEMP 1” (A/T fluid temperature sensor signal) indicates more than 60°C (140°F).
–For M/T models: After the engine is warmed up to normal operating temperature, drive vehicle for 5 min-
utes.

Electrical load: Not applied
–Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.

Engine speed: Idle
Inspection ProcedureNBS0003T
NOTE:
Perform “SPEC” in “DATA MONITOR” mode in maximum scale display.
1. Perform EC-71, "
Basic Inspection" .
2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2”, “MAS A/F SE-B1” and “MAS A/F SE-B2” in
“SPEC” of ”DATA MONITOR” mode with CONSULT-III.
4. Make sure that monitor items are within the SP value.
5. If NG, go to EC-133, "
Diagnostic Procedure" .

TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-137
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11 . CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> GO TO 12.
12. CHECK A/F SENSOR 1 FUNCTION
Perform all DTC Confirmation Procedure related with A/F sensor 1.

For DTC P0130, P0150, refer to EC-248, "DTC Confirmation Procedure" .

For DTC P0131, P0151, refer to EC-267, "DTC Confirmation Procedure" .

For DTC P0132, P0152, refer to EC-660, "DTC Confirmation Procedure" .

For DTC P0133, P0153, refer to EC-276, "DTC Confirmation Procedure" .

For DTC P2A00, P2A03, refer to EC-660, "DTC Confirmation Procedure" .
OK or NG
OK >> GO TO 15.
NG >> GO TO 13.
13. CHECK A/F SENSOR 1 CIRCUIT
Perform Diagnostic Procedure according to corresponding DTC.
>> GO TO 14.
14. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> GO TO 15.
15. DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect ECM harness connector. Check pin terminal and connector for damage, and then reconnect it.
>> GO TO 16.
16. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG >> Detect malfunctioning part according to EC-90, "
Symptom Matrix Chart" .

EC-138
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Revision: 2006 November2007 350Z
17. CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of "DATA MONITOR" mode, and make sure that the indication is within the
SP value.
OK or NG
OK >>INSPECTION END
NG (More than the SP value)>>GO TO 18.
NG (Less than the SP value)>>GO TO 25.
18. DETECT MALFUNCTIONING PART
1. Check for the cause of large engine friction. Refer to the following.
–Engine oil level is too high
–Engine oil viscosity
–Belt tension of power steering, alternator, A/C compressor, etc. is excessive
–Noise from engine
–Noise from transmission, etc.
2. Check for the cause of insufficient combustion. Refer to the following.
–Valve clearance malfunction
–Intake valve timing control function malfunction
–Camshaft sprocket installation malfunction, etc.
>> Repair or replace malfunctioning part, and then GO TO 30.
19. CHECK INTAKE SYSTEM
Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system
OK or NG
OK >> GO TO 21.
NG >> Repair or replace malfunctioning part, and then GO TO 20.
20. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”, AND “B/FUEL SCHDL”
Select “A/F ALPHA-B1”, “A/F ALPHA-B2”, and “B/FUEL SCHDL” in “SPEC” of "DATA MONITOR" mode, and
make sure that the each indication is within the SP value.
OK or NG
OK >>INSPECTION END
NG (“B/FUEL SCHDL” is more, “A/F ALPHA-B1”, “A/F ALPHA-B2” are less than the SP value)>>GO TO 21.
21. DISCONNECT AND RECONNECT MASS AIR FLOW SENSOR HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect mass air flow sensor harness connector. Check pin terminal and connector for damage and
then reconnect it again.
>> GO TO 22.