Diagnosis Procedure

WARNING: This page is about a different car, the 2013 Nissan Armada. However, it is still accessible from the selected car via links, so may be relevant.

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

OK or NG

OK: GO TO 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: Checking Exhaust Gas Leakage
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  OK or NG
  
  OK: GO TO 3.
  
  NG: Repair or replace.
CHECK INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.

OK or NG

OK: GO TO 4.

NG: Repair or replace.

CHECK IGNITION TIMING

Check the following items. Refer to "BASIC INSPECTION ".

Items	Specifications
Target idle speed	650 ± 50 RPM (in P or N position)
Ignition timing	15 ± 5° BTDC (in P or N position)

OK or NG

OK: GO TO 5.

NG: Follow the "BASIC INSPECTION ".

CHECK FUEL INJECTOR
1. Stop engine and then turn ignition switch ON.
2. Check voltage between ECM terminals 21, 22, 23, 40, 41, 42, 44, 63 and ground with CONSULT or tester.
  Refer to Wiring Diagram for fuel injector, "WIRING DIAGRAM ".
  
  Battery voltage should exist.
  
  Fig 2: Checking Voltage Between ECM Terminals 21, 22, 23, 40, 41, 42, 44, 63 And Ground
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  OK or NG
  
  OK: GO TO 6.
  
  NG: Perform "DIAGNOSIS PROCEDURE ".
CHECK FUNCTION OF IGNITION COIL-I
CAUTION: Do the following procedure in the place where ventilation is good without the combustible.
1. Turn ignition switch OFF.
2. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
  NOTE: Do not use CONSULT 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.
  
  Fig 3: Identifying Fuel Pump Fuse And IPDM E/R
  Courtesy of NISSAN NORTH AMERICA, INC.
7. Remove ignition coil and spark plug of the cylinder to be checked. Refer to "REMOVAL AND INSTALLATION " and.
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 below.
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.
  
  Fig 4: Measuring Gap Between Spark Plug And Grounded Metal Portion Using Rope
  Courtesy of NISSAN NORTH AMERICA, INC.
  CAUTION:
  - During the operation, always stay 0.5 m (1.6 ft) or more away from spark plug and the ignition coil. Be careful not to get an electrical shock while checking, because the electrical discharge voltage becomes 20 kV 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.
  
  OK or NG
  
  OK: GO TO 10.
  
  NG: GO TO 7.
CHECK FUNCTION OF IGNITION COIL-II
1. Turn ignition switch OFF.
2. Disconnect spark plug and connect a known-good 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.
  
  OK or NG
  
  OK: GO TO 8.
  
  NG: Check ignition coil, power transistor and their circuits. Refer to "WIRING DIAGRAM ".
CHECK SPARK PLUG
Check the initial spark plug for fouling, etc.

OK or NG

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

NG:
1. Repair or clean spark plug.
2. GO TO 9.
  
  Fig 5: Identifying Spark Plug Fouling Area
  Courtesy of NISSAN NORTH AMERICA, INC.
CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for about 3 seconds, and recheck whether spark is generated between the spark plug and the grounded portion.
  Spark should be generated.
  
  OK or NG
  
  OK: INSPECTION END
  
  NG: Replace malfunctioning spark plug(s) with standard type one(s). For spark plug type, refer to "REMOVAL AND INSTALLATION ".
CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Remove fuel injector assembly. Refer to "REMOVAL AND INSTALLATION ".
  Refer to "REMOVAL AND INSTALLATION ".
  
  Keep fuel hose and all fuel injectors connected to fuel injector gallery.
3. Disconnect all ignition coil harness connectors.
4. Reconnect all fuel injector harness connectors disconnected.
5. Turn ignition switch ON.
  Make sure fuel does not drip from fuel injector.
  
  OK or NG
  
  OK (Does not drip.): GO TO 11.
  
  NG (Drips.): Replace the fuel injector(s) from which fuel is dripping. Refer to FUEL INJECTOR AND FUEL TUBE .
CHECK INTERMITTENT INCIDENT
Refer to "HOW TO CHECK TERMINAL " and "INTERMITTENT INCIDENT ".

Trouble is fixed.: INSPECTION END

Trouble is not fixed.: Replace three way catalyst assembly. Refer to EXHAUST MANIFOLD AND THREE WAY CATALYST .