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Home >> Infiniti >> 2017 >> QX80 Base, RWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Symptom Diagnosis & Removal And Installation) >> Symptom Diagnosis >> 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 COMPONENT FUNCTION CHECK
Fuel pressure regulator system 3 3 4 4 4 4 4 4 4   4     WORK PROCEDURE
Fuel injector circuit 1 1 2 3 2   2 2     2     COMPONENT FUNCTION CHECK
Evaporative emission system 3 3 4 4 4 4 4 4 4   4     INSPECTION 
FRP sensor circuit 1 1 2 2 2   2 2     2     DTC LOGIC
DTC LOGIC
High pressure fuel pump circuit     4   3                 COMPONENT FUNCTION CHECK
Air Positive crankcase ventilation system 3 3 4 4 4 4 4 4 4   4 1   INSPECTION 
Incorrect idle speed adjustment       1 1 1 1   1     WORK PROCEDURE
Electric throttle control actuator 1 1 2 3 3 2 2 2 2   2   2 DTC LOGIC
DTC LOGIC
Ignition Incorrect ignition timing adjustment 3 3 1 1 1   1 1     1     WORK PROCEDURE
Ignition circuit 1 1 2 2 2   2 2     2     COMPONENT FUNCTION CHECK
Main power supply and ground circuit 2 2 3 3 3   3 3   2 3     DIAGNOSIS PROCEDURE
Mass air flow sensor circuit 1 1 2 2 2   2 2     2     DTC LOGIC
Engine coolant temperature sensor 1 circuit 3 3 3       DTC LOGIC
Air fuel ratio (A/F) sensor 1 circuit             DTC LOGIC
DTC LOGIC
DTC LOGIC
DTC LOGIC
DTC LOGIC
Throttle position sensor circuit     2 2       DTC LOGIC
DTC LOGIC
DTC LOGIC
DTC LOGIC
DTC LOGIC
Accelerator pedal position sensor circuit     3 2 1             DTC LOGIC
DTC LOGIC
DTC LOGIC
Knock sensor circuit     2               3     DTC LOGIC
Engine oil temperature sensor     4   2           3     DTC LOGIC
Engine oil pressure sensor     4   4 3 3 3     3     DTC LOGIC
Crankshaft position sensor circuit 2 2                       DTC LOGIC
Camshaft position sensor circuit 3 2                       DTC LOGIC
Vehicle speed signal circuit   2 3   3           3     DESCRIPTION
Power steering pressure sensor circuit   2         3 3           DTC LOGIC
ECM 2 2 3 3 3 3 3 3 3 3 3     -
Intake valve timing control solenoid valve circuit   3 2   1 3 2 2 3   3     DTC LOGIC
Exhaust valve timing control solenoid valve circuit   3 2   1 3 2 2 3   3     DTC LOGIC
DTC LOGIC
Exhaust valve timing control position sensor 5 5 5 5 5   5 5     5     DTC LOGIC
Exhaust gas temperature sensor                     5     DTC LOGIC
DTC LOGIC
VVEL control module 3   4 4 3                 DTC LOGIC
DTC LOGIC
VVEL actuator motor 3   4 4 3                 DTC LOGIC
VVEL actuator motor relay 3   4 4 3                 DTC LOGIC
VVEL control shaft position sensor 3   4 4 3                 DTC LOGIC
PNP signal circuit     3   3   3 3     3     DTC LOGIC
Refrigerant pressure sensor circuit   2       3     3   4     COMPONENT FUNCTION CHECK
Electrical load signal circuit             3             COMPONENT FUNCTION CHECK
Air conditioner circuit 2 2 3 3 3 3 3 3 3   3   2 DIAGNOSIS CHART BY SYMPTOM
ABS actuator and electric unit (control unit)     4                     WORK FLOW
Battery current sensor           4 5 5         3 DTC LOGIC
DTC LOGIC
DTC LOGIC
Heated oxygen sensor 2     6   6   6 6     5     DTC LOGIC
DTC LOGIC
COMPONENT INSPECTION (HO2 SENSOR 2)

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

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