Diagnostic Procedure

CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dent.

OK or NG
1. OK: GO TO 2.
2. NG: Repair or replace.
CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before the three way catalyst (manifold).
  
  Fig 1: Identifying Exhaust Gas Leak
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
1. OK: GO TO 3.
2. NG: Repair or replace.
CHECK INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.

OK or NG
1. OK: GO TO 4.
2. NG: Repair or replace.
CHECK IGNITION TIMING
Check the following items. Refer to BASIC INSPECTION .

Fig 2: Checking Ignition Timing
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 5.
2. NG: Follow the Basic Inspection.
CHECK INJECTORS
1. Refer to WIRING DIAGRAM for Injectors, .
2. Stop engine and then turn ignition switch ON.
3. Check voltage between ECM terminals 1, 2, 3, 11, 12, 13 and ground with CONSULT-II or tester.
  
  Fig 3: Checking Voltage Between ECM Terminals Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
1. OK: GO TO 6.
2. NG: Perform DIAGNOSTIC PROCEDURE .
CHECK IGNITION SPARK
1. Turn ignition switch OFF.
2. Disconnect ignition coil assembly from rocker cover.
3. Connect a known good spark plug to the ignition coil assembly.
4. Place end of spark plug against a suitable ground and crank engine.
5. Check for spark.
  
  Fig 4: Checking Ignition Spark Plug
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
1. OK: GO TO 7.
2. NG: Check ignition coil with power transistor and their circuit. Refer to IGNITION SIGNAL .
CHECK INJECTOR
1. Turn ignition switch OFF.
2. Remove injector assembly.
  Refer to INJECTOR .
  
  Keep fuel hose and all injectors connected to injector gallery.
3. Disconnect all ignition coil harness connectors.
4. Turn ignition switch ON.
  Make sure fuel does not drip from injector.
OK or NG
1. OK (Does not drip.): GO TO 8.
2. NG (Drips.): Replace the injector(s) from which fuel is dripping.
CHECK INTERMITTENT INCIDENT
Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .
1. Trouble is fixed.: INSPECTION END
2. Trouble is not fixed.: Replace three way catalyst (manifold).