Infiniti M35/M45 Y50. Manual - part 419

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

EC-149

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16. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1.

Start engine.

2.

Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” 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-99, "Symptom Matrix Chart"

 .

17. 

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” 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.

PBIB2332E

EC-150

[VQ35DE]

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

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 “DATA MONITOR (SPEC)” 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.

22. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1.

Start engine.

2.

Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” 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-202, "DTC

P0102, P0103 MAF SENSOR"

 .

2. GO TO 29.

NG

>> GO TO 23.

23. 

CHECK “MAS A/F SE-B1”

Select “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” 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 IVIS(NATS) system and registration of all IVIS(NATS) ignition key IDs. Refer to

BL-248, "ECM Re-Communicating Function"

 .

3.

Perform 

EC-85, "VIN Registration"

 .

4.

Perform 

EC-86, "Accelerator Pedal Released Position Learning"

 .

5.

Perform 

EC-86, "Throttle Valve Closed Position Learning"

 .

6.

Perform 

EC-86, "Idle Air Volume Learning"

 .

>> GO TO 29.

PBIB2370E

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

EC-151

[VQ35DE]

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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 “DATA MONITOR (SPEC)” 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.

27. 

CHECK “MAS A/F SE-B1”

Select “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” 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 “DATA MONITOR (SPEC)” 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-99, "Symptom Matrix Chart"

 .

PBIB2370E

EC-152

[VQ35DE]

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

30. 

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” 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-99, "Symptom Matrix Chart"

 .