1.CHECK EXHAUST SYSTEM Visually check exhaust tubes and muffler for dents. Is the inspection result normal? YES>>GO TO 2. NO>>Repair or replace malfunctioning part.
2.CHECK EXHAUST GAS LEAK

1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before the three way catalyst 1.

Is exhaust gas leak detected?
YES>>Repair or replace malfunctioning part.
NO>>GO TO 3.
3.CHECK INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected?
YES>>Repair or replace malfunctioning part.
NO>>GO TO 4.
4.CHECK IDLE SPEED AND IGNITION TIMING
Check idle speed and ignition timing.
For procedure, refer to Special Repair Requirement (GT-R certified NISSAN dealer).
For specification, refer to Idle Speed and Ignition Timing.
Is the inspection result normal?
YES>>GO TO 5.
NO>>Follow the Special Repair Requirement (GT-R certified NISSAN dealer).
5.CHECK FUEL INJECTORS

1. Stop engine and then turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals as follows.

   ECM | Voltage
   + | –
   Connector | Terminal | Connector | Terminal
   F101 | 17 | M107 | 128 | Battery voltage
   21
   25
   37
   41
   45

Is the inspection result normal?
YES>>GO TO 6.
NO>>Perform Diagnosis Procedure (GT-R certified NISSAN dealer).
6.CHECK FUNCTION OF IGNITION COIL-I
■ CAUTION ■
Perform the following procedure in a place with no combustible objects and good ventilation.

1. Turn ignition switch OFF.
2. Remove fuel pump fuse (1) in IPDM E/R (2) to release fuel pressure.
   NOTE：
   Do not use CONSULT-III to release fuel pressure, or fuel pressure applies again during the following procedure.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
6. Remove all ignition coil harness connectors to avoid the electrical discharge from the ignition coils.
7. Remove ignition coil and spark plug of the cylinder to be checked.
8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
9. Connect spark plug and harness connector to ignition coil.
10. 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.
11. Crank engine for about 3 seconds, and check whether spark is generated between the spark plug and the grounded metal portion.

    Spark should be generated.

    ■ CAUTION ■
    - Do not place to the spark plug and the ignition coil within 0.5 m (1.6 ft) each other. Be careful not to get an electrical shock while checking, because the electrical discharge voltage becomes 20 kV or more.
    - It might to damage the ignition coil if the gap of more than 17 mm (0.66 in) is made.
    NOTE：
    When the gap is less than 13 mm (0.52 in), a spark might be generated even if the coil is malfunctioning.

Is the inspection result normal?
YES>>GO TO 10.
NO>>GO TO 7.
7.CHECK FUNCTION OF IGNITION COIL-II

1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a non-malfunctioning spark plug.
3. 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 (GT-R certified NISSAN dealer).
8.CHECK SPARK PLUG
Check the initial spark plug for fouling, etc.
Is the inspection result normal?
YES>>Replace spark plug(s) with standard type one(s). For spark plug type, refer to Spark Plug.
NO>>Repair or clean spark plug. Then GO TO 9.
9.CHECK FUNCTION OF IGNITION COIL-III

1. Reconnect the initial spark plugs.
2. 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 Spark Plug.
10.CHECK FUEL INJECTOR

1. Turn ignition switch OFF.
2. Remove fuel injector assembly.Refer to Removal and Installation (GT-R certified NISSAN dealer).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>>Replace the fuel injector(s) from which fuel is dripping.
NO>>GO TO 11.
11.CHECK INTERMITTENT INCIDENT
Refer to Intermittent Incident.
Is the trouble fixed?
YES>>INSPECTION END
NO>>Replace three way catalyst assembly.