Diagnosis Procedure

INSPECTION START
Which malfunction (A or B) is duplicated?

A or B

A : GO TO 3.

B : GO TO 2.
CHECK INTAKE AIR LEAK
Check the following for connections.
- Air duct
- Vacuum hoses
- Intake air passage between air duct and intake manifold
  OK or NG
  
  OK : GO TO 3.
  
  NG : Reconnect the parts.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body.
  Refer to "GROUND INSPECTION ".
  
  Fig 1: Identifying Ground Connections Components
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
  
  OK : GO TO 4.
  
  NG : Repair or replace ground connections.
CHECK MAF SENSOR POWER SUPPLY CIRCUIT
1. Disconnect mass air flow (MAF) sensor (1) harness connector.
2. Turn ignition switch ON.
  
  Fig 2: Identifying Mass Air Flow (MAF) Sensor Harness Connector
  Courtesy of NISSAN MOTOR CO., U.S.A.
3. Check voltage between MAF sensor terminal 2 and ground with CONSULT-III or tester.
  Voltage: Battery voltage
  
  Fig 3: Checking Voltage Between MAF Sensor Terminal 2 And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
  
  OK : GO TO 6.
  
  NG : GO TO 5.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E8, F8
- Harness for open or short between mass air flow sensor and IPDM E/R
- Harness for open or short between mass air flow sensor and ECM
  Repair open circuit or short to ground or short to power in harness or connectors.
CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between MAF sensor terminal 3 and ECM terminal 52.
  Refer to Wiring Diagram.
  
  Continuity should exist .
4. Also check harness for short to ground and short to power.
  OK or NG
  
  OK : GO TO 7.
  
  NG : Repair open circuit or short to ground or short to power in harness or connectors.
CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between MAF sensor terminal 4 and ECM terminal 45.
  Refer to Wiring Diagram.
  
  Continuity should exist .
2. Also check harness for short to ground and short to power.
  OK or NG
  
  OK : GO TO 8.
  
  NG : Repair open circuit or short to ground or short or short to power in harness or connectors.
CHECK INTAKE AIR TEMPERATURE SENSOR
Refer to "COMPONENT INSPECTION ".

OK or NG

OK : GO TO 9.

NG : Replace intake air temperature sensor.
CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to "COMPONENT INSPECTION ".

OK or NG

OK : GO TO 10.

NG : Replace EVAP control system pressure sensor.
CHECK MASS AIR FLOW SENSOR
Refer to "COMPONENT INSPECTION ".

OK or NG

OK : GO TO 11.

NG : Replace mass air flow sensor.
CHECK INTERMITTENT INCIDENT
Perform TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

INSPECTION END