Diagnosis Procedure

Visually check exhaust tubes and muffler for dent.

Is the inspection result normal? 

YES : GO TO 2.

NO : Repair or replace.

1. Activate "INSPECTION MODE 1 " to start engine.
2. Listen for an exhaust gas leak before the three way catalyst (manifold).
   Fig 1: Checking Exhaust Gas For Leakage

   Courtesy of NISSAN MOTOR CO., U.S.A.

Is exhaust gas leak detected? 

YES : Repair or replace.

NO : GO TO 3.

Listen for an intake air leak after the mass air flow sensor.

Is intake air leak detected? 

YES : Repair or replace.

NO : GO TO 4.

1. Check idle speed.
   • For procedure, refer to "IDLE SPEED : Special Repair Requirement ".
   • For specification, refer to "IDLE SPEED ".
2. Check ignition timing.
   • For procedure, refer to "IGNITION TIMING : Special Repair Requirement ".
   • For specification, refer to "IGNITION TIMING ".

Is the inspection result normal? 

YES : GO TO 5.

NO : Follow the "BASIC INSPECTION : Special Repair Requirement ".

1. Turn ignition switch OFF and then turn ON.
2. Check the voltage between ECM harness connector and ground.
   TERMINALS VOLTAGE REFERENCE
   
   

   ECM		Ground	Voltage
   Connector	Terminal
   F14	29	Ground	Battery voltage
   	30
   	31
   	32

Is the inspection result normal? 

YES : GO TO 6.

NO : Perform "DIAGNOSIS PROCEDURE ".

1. Turn ignition switch OFF.
2. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
   NOTE: Do not use CONSULT-III to release fuel pressure, or fuel pressure applies again during the following procedure.
3. Turn ignition switch ON (READY).
4. Depress accelerator pedal and keep it.
5. After engine stalls, check DTC.

   If DTC is detected, erase DTC and go to next steps.

   If DTC is not detected, go to next steps.

6. Turn ignition switch OFF.
7. Remove all ignition coil harness connectors to avoid the electrical discharge from the ignition coils.
8. Remove ignition coil and spark plug of the cylinder to be checked.
9. Repeat steps  3 to  5 for two or three times to remove combustion gas in the cylinder.
10. Connect spark plug and harness connector to ignition coil.
11. Fix ignition coil using a rope etc. with gap of 13 - 17 mm (0.52 - 0.66 in) between the edge of the spark plug and grounded metal portion as shown in the figure.
12. Turn ignition switch ON (READY).
13. Depress accelerator pedal for about 3 seconds, and check whether spark is generated between the spark plug and the grounded metal portion.

    Spark should be generated. 

    Fig 2: Checking For Spark

    Courtesy of NISSAN MOTOR CO., U.S.A.
    CAUTION:

    • Do not approach to the spark plug and the ignition coil within 50 cm (19.7 in). Be careful not to get an electrical shock while checking, because the electrical discharge voltage becomes 20kV or more.
    • It might cause to damage the ignition coil if the gap of more than 17 mm (0.66 in) is taken.
    NOTE: When the gap is less than 13 mm (0.52 in), the spark might be generated even if the coil is malfunctioning.

Is the inspection result normal? 

YES : GO TO  10.

NO : GO TO 7.

1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a known-good spark plug.
3. Turn ignition switch ON (READY).
4. Depress the accelerator pedal to crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and the grounded metal portion.

   Spark should be generated. 

Is the inspection result normal? 

YES : GO TO 8.

NO : Check ignition coil, power transistor and their circuits. Refer to "DIAGNOSIS PROCEDURE ".

Check the initial spark plug for fouling, etc.

Fig 3: Checking Spark Plug For Fouling

Courtesy of NISSAN MOTOR CO., U.S.A.

Is the inspection result normal? 

YES : Replace spark plug(s) with standard type one(s). For spark plug type, refer to "REMOVAL AND INSTALLATION ".

NO : Repair or clean spark plug. Then GO TO 9.

1. Reconnect the initial spark plugs.
2. Turn ignition switch ON (READY).
3. Depress the accelerator pedal to crank engine for about three seconds, and recheck whether spark is generated between the spark plug and the grounded portion.

   Spark should be generated. 

Is the inspection result normal? 

YES : INSPECTION END

NO : Replace spark plug(s) with standard type one(s). For spark plug type, refer to "REMOVAL AND INSTALLATION ".

1. Turn ignition switch OFF.
2. Remove fuel injector assembly.

   Refer to "REMOVAL AND INSTALLATION ".

   Keep fuel hose and all fuel injectors connected to fuel tube.

3. Disconnect all ignition coil harness connectors.
4. Reconnect all fuel injector harness connectors disconnected.
5. Turn ignition switch ON.

Does fuel drip from fuel injector? 

YES : GO TO 11.

NO : Replace the fuel injector(s) from which fuel is dripping.

Refer to "INTERMITTENT INCIDENT ".

Is the trouble fixed? 

YES : INSPECTION END

NO : Replace three way catalyst assembly.