Diagnosis Procedure

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

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 Leak
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	M/T: 625 ± 50 RPM (in Neutral position) A/T: 625 ±
Ignition timing	M/T: 15 ± 5° BTDC (in Neutral position) A/T: 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 and ground with CONSULT or tester.
Refer to Wiring Diagram for FUEL INJECTOR, "WIRING DIAGRAM ".

Battery voltage should exist.

OK or NG

OK: GO TO 6.

NG: Perform "DIAGNOSIS PROCEDURE ".

Fig 2: Checking Voltage Between ECM Terminals 21, 22, 23, 40, 41, 42 And Ground
Courtesy of NISSAN NORTH AMERICA, INC.
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 (No. 48) 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.
7. Remove ignition coil and spark plug of the cylinder to be checked.
  
  Fig 3: Identifying Fuel Pump Fuse And IPDM E/R
  Courtesy of NISSAN NORTH AMERICA, INC.
8. Crank engine for five 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 between the edge of the spark plug and grounded metal portion as shown in the figure.
11. Crank engine for about three seconds, and check whether spark is generated between the spark plug and the grounded metal portion.
Spark should be generated.

Fig 4: Identifying Gap Between Edge Of Spark Plug And Grounded Metal Portion
Courtesy of NISSAN NORTH AMERICA, INC.
CAUTION:
- Never place to the spark plug and the ignition coil within 50cm (19.7 in) each other. 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 made.
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 approximately 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 IGNITION SIGNAL .
CHECK SPARK PLUG
Check the initial spark plug for fouling, etc.

OK or NG

OK: Replace 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 Initial Spark Plug For Fouling
Courtesy of NISSAN NORTH AMERICA, INC.
CHECK FUNCTION OF IGNITION COIL-III
1. Reconnect the initial spark plugs.
2. Crank engine for approximately 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 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 ".
  
  Keep fuel hose and all fuel injectors connected to fuel tube.
3. Reconnect all fuel injector harness connectors.
4. Disconnect all ignition coil harness connectors.
5. Turn ignition switch ON.
Check that 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 "EXPLODED VIEW ".
CHECK INTERMITTENT INCIDENT
Refer to "INTERMITTENT INCIDENT ".

Trouble is fixed: INSPECTION END

Trouble is not fixed: Replace three way catalyst (manifold). Refer to "REMOVAL AND INSTALLATION (THREE WAY CATALYST) ".