NISSAN 350Z 2007 Z33 Engine Control Workshop Manual
Manufacturer: NISSAN, Model Year: 2007, Model line: 350Z, Model: NISSAN 350Z 2007 Z33Pages: 720
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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.
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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" .
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TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-133
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Diagnostic ProcedureNBS0003U
OVERALL SEQUENCE
PBIB2268E
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EC-134
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Revision: 2006 November2007 350Z
PBIB3531E
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TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-135
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DETAILED PROCEDURE
1. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Confirm that the testing conditions are met. Refer to EC-132, "
Testing Condition" .
3. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” in mode, and make sure that the each indication is
within the SP value.
NOTE:
Check “A/F ALPHA-B1”, “A/F ALPHA-B2” for approximately 1 minute because they may fluctuate. It is NG
if the indication is out of the SP value even a little.
OK or NG
OK >> GO TO 17.
NG (Less than the SP value)>>GO TO 2.
NG (More than the SP value)>>GO TO 3.
2. 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 >> GO TO 4.
NG (More than the SP value)>>GO TO 19.
3. 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 >> GO TO 6.
NG (More than the SP value)>>GO TO 6.
NG (Less than the SP value)>>GO TO 25.
4. CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Stop the engine.
2. Disconnect PCV hose, and then plug it.
3. Start engine.
4. 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 >> GO TO 5.
NG >> GO TO 6.
5. CHANGE ENGINE OIL
1. Stop the engine.
2. Change engine oil.
NOTE:
This symptom may occur when a large amount of gasoline is mixed with engine oil because of driving
conditions (such as when engine oil temperature does not rise enough since a journey distance is too
short during winter). The symptom will not be detected after changing engine oil or changing driving con-
dition.
>>INSPECTION END
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EC-136
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Revision: 2006 November2007 350Z
6. CHECK FUEL PRESSURE
Check fuel pressure. (Refer to EC-79, "
Fuel Pressure Check" .)
OK or NG
OK >> GO TO 9.
NG (Fuel pressure is too high)>>Replace fuel pressure regulator, refer to EC-79, "
Fuel Pressure Check" .
GO TO 8.
NG (Fuel pressure is too low)>>GO TO 7.
7. DETECT MALFUNCTIONING PART
1. Check the following.
–Clogged and bent fuel hose and fuel tube
–Clogged fuel filter
–Fuel pump and its circuit (Refer to EC-691, "FUEL PUMP" .)
2. If NG, repair or replace the malfunctioning part. (Refer to EC-79, "
Fuel Pressure Check" .)
If OK, replace fuel pressure regulator.
>> GO TO 8.
8. 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 9.
9. PERFORM POWER BALANCE TEST
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode.
2. Make sure that the each cylinder produces a momentary engine speed drop.
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
10. DETECT MALFUNCTIONING PART
1. Check the following.
–Ignition coil and its circuit (Refer to EC-698, "IGNITION SIGNAL" .)
–Fuel injector and its circuit (Refer to EC-686, "FUEL INJECTOR" .)
–Intake air leakage
–Low compression pressure (Refer to EM-89, "CHECKING COMPRESSION PRESSURE" .)
2. If NG, repair or replace the malfunctioning part.
If OK, replace fuel injector. (It may be caused by leakage from fuel injector or clogging.)
>> GO TO 11.
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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" .
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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.
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22. 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 >> 1. Detect malfunctioning part of mass air flow sensor circuit and repair it.
Refer to EC-197, "
DTC P0101, P010B MAF SENSOR" .
2. GO TO 29.
NG >> GO TO 23.
23. CHECK “MAS A/F SE-B1”, “MAS A/F SE-B2”
Select “MAS A/F SE-B1”, “MAS A/F SE-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
indication is within the SP value.
OK or NG
OK >> GO TO 24.
NG (More than the SP value)>>Replace mass air flow sensor, and then GO TO 29.
24. REPLACE ECM
1. Replace ECM.
2. Perform initialization of NVIS(NATS) system and registration of all NVIS(NATS) ignition key IDs.
Refer to BL-152, "
ECM Re-communicating Function" .
3. Perform EC-76, "
VIN Registration" .
4. Perform EC-76, "
Exhaust Valve Timing Control Learning" .
5. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
6. Perform EC-77, "
Throttle Valve Closed Position Learning" .
7. Perform EC-77, "
Idle Air Volume Learning" .
>> GO TO 29.
25. 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 27.
NG >> Repair or replace malfunctioning part, and then GO TO 26.
26. 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 (Less than the SP value)>>GO TO 27.
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EC-140
TROUBLE DIAGNOSIS - SPECIFICATION VALUE
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27. CHECK “MAS A/F SE-B1”, “MAS A/F SE-B2”
Select “MAS A/F SE-B1”, “MAS A/F SE-B2” in “SPEC” of "DATA MONITOR" mode, and make sure that the
indication is within the SP value.
OK or NG
OK >> GO TO 28.
NG (Less than the SP value)>>Replace mass air flow sensor, and then GO TO 30.
28. CHECK INTAKE SYSTEM
Check for the cause of air leak after the mass air flow sensor. Refer to the following.
Disconnection, looseness, and cracks in air duct
Looseness of oil filler cap
Disconnection of oil level gauge
Open stuck, breakage, hose disconnection, or cracks of PCV valve
Disconnection or cracks of EVAP purge hose, open stuck of EVAP canister purge volume control solenoid
valve
Malfunctioning seal of rocker cover gasket
Disconnection, looseness, or cracks of hoses, such as vacuum hose, connecting to intake air system
parts
Malfunctioning seal of intake air system, etc.
>> GO TO 30.
29. 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 >> Detect malfunctioning part according to EC-90, "
Symptom Matrix Chart" .
30. CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of "DATA MONITOR" mode, and then make sure that the indication is
within the SP value.
OK or NG
OK >>INSPECTION END
NG >> Detect malfunctioning part according to EC-90, "
Symptom Matrix Chart" .