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Home >> Infiniti >> 2021 >> Q60 Pure, AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (Diagnostics) (3 Of 4) >> Symptom Diagnosis >> Engine Control System >> Engine Control System Symptoms >> Symptom Table >> System -- Basic Engine Control System
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System -- Basic Engine Control System

SYMPTOM

Reference

HARD/NO START/RESTART (EXCP. HA)

ENGINE STALL

HESITATION/SURGING/FLAT SPOT

SPARK KNOCK/DETONATION

LACK OF POWER/POOR ACCELERATION

HIGH IDLE/LOW IDLE

ROUGH IDLE/HUNTING

IDLING VIBRATION

SLOW/NO RETURN TO IDLE

OVERHEATS/WATER TEMPERATURE HIGH

EXCESSIVE FUEL CONSUMPTION

EXCESSIVE OIL CONSUMPTION

BATTERY DEAD (UNDER CHARGE)

Warranty symptom code

AA

AB

AC

AD

AE

AF

AG

AH

AJ

AK

AL

AM

HA

Fuel

Low pressure fuel pump circuit

1

1

2

3

2

2

2

3

2

Refer to Component Function Check .

Fuel pressure regulator system

3

3

4

4

4

4

4

4

4

4

Refer to Work Procedure .

Fuel injector circuit

1

1

2

3

2

2

2

2

Refer to Component Function Check .

Evaporative emission system

3

3

4

4

4

4

4

4

4

4

Refer to System Description .

FRP sensor circuit

1

1

2

2

2

2

2

2

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

High pressure fuel pump circuit

4

3

Refer to DTC Description .

Air

Positive crankcase ventilation system

3

3

4

4

4

4

4

4

4

4

1

Refer to POSITIVE CRANKCASE VENTILATION : Periodic Maintenance Operation .

Incorrect idle speed adjustment

1

1

1

1

1

Refer to Work Procedure .

Electric throttle control actuator

1

1

2

3

3

2

2

2

2

2

2

Refer to DTC Description , refer to DTC Description .

Ignition

Incorrect ignition timing adjustment

3

3

1

1

1

1

1

1

Refer to Work Procedure .

Ignition circuit

1

1

2

2

2

2

2

2

Refer to Component Function Check .

Main power supply and ground circuit

2

2

3

3

3

3

3

2

3

Refer to Diagnosis Procedure .

Mass air flow sensor circuit

1

1

2

2

2

2

2

2

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Engine coolant temperature sensor circuit

3

3

3

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Air fuel ratio (A/F) sensor 1 circuit

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Throttle position sensor circuit

2

2

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Accelerator pedal position sensor circuit

3

2

1

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Heated oxygen sensor 2 circuit

6

6

6

6

5

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Knock sensor circuit

2

3

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Engine oil temperature sensor circuit

4

2

3

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Engine oil pressure sensor circuit

4

4

3

3

3

3

Refer to DTC Description .

Crankshaft position sensor circuit

2

2

Refer to DTC Description .

Intake camshaft position sensor circuit

3

2

3

Refer to DTC Description , refer to DTC Description .

Exhaust camshaft position sensor circuit

2

2

3

3

3

Refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure .

Turbocharger boost sensor circuit

3

3

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Manifold absolute pressure sensor circuit

2

Refer to DTC Description ,

Refer to DTC Description .

Vehicle speed signal circuit

2

3

3

3

Refer to DTC Description .

ECM

2

2

3

3

3

3

3

3

3

3

3

--

Electric intake valve timing control module circuit

3

3

3

Refer to Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure .

Electric intake valve timing control actuator circuit

3

Refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure , refer to DTC Diagnosis Procedure .

Exhaust valve timing control solenoid valve circuit

2

2

2

2

2

2

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

PNP signal circuit

3

3

3

3

3

Refer to DTC Description .

Refrigerant pressure sensor circuit

2

3

3

4

Refer to Component Function Check .

Electric wastegate control actuator circuit

1

Refer to DTC Description ,

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description ,

Refer to DTC Description ,

Refer to DTC Description ,

Refer to DTC Description ,

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Battery current sensor circuit

4

5

5

3

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Refer to DTC Description .

Electrical load signal circuit

3

Refer to Component Function Check .

Air conditioner circuit

2

2

3

3

3

3

3

3

3

3

2

Refer to Work Flow .

ABS actuator and electric unit (control unit)

4

Refer to Work Flow .

1 - 6: The numbers refer to the order of inspection.

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