EC-352
[VQ35DE]
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
Revision: 2007 April2007 M35/M45
4. CHECK FUNCTION OF FUEL INJECTOR-I
Without CONSULT-II
1. Turn ignition switch OFF.
2. Disconnect harness connectors F221 (1), F33 (2).
–: vehicle front
–Cylinder head (bank 2) (3)
3. Turn ignition switch ON.
4. Check voltage between harness connector F33 terminal 5 and
ground with CONSULT-II or tester.
5. Turn ignition switch OFF.
6. Disconnect ECM harness connector.
7. Check harness continuity between the following terminals.
8. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to EC-669, "
FUEL INJECTOR" .
PBIB2785E
Voltage: Battery voltage
Cylinder Harness connector F33 terminal ECM terminal
16 23
24 42
32 22
43 41
51 21
67 40
Continuity should exist.
PBIB2323E
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
EC-353
[VQ35DE]
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Revision: 2007 April2007 M35/M45
5. CHECK FUNCTION OF FUEL INJECTOR-II
Provide battery voltage between the following terminals, and then
interrupt it. Listen to each fuel injector operating sound.
OK or NG
OK >> GO TO 6.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to EC-669, "
FUEL INJECTOR" .
CylinderHarness connector F221 terminal
(+) (–)
1
56
24
32
43
51
67
Operating sound should exist.
PBIB2497E
EC-354
[VQ35DE]
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
Revision: 2007 April2007 M35/M45
6. 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 (1) in IPDM E/R (2) to release fuel pres-
sure.
NOTE:
Do not use CONSULT-II to release fuel pressure, or fuel pres-
sure 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 electri-
cal 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
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 por-
tion.
CAUTION:
Do not approach to the spark plug and the ignition coil
within 50cm. 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 is taken.
NOTE:
When the gap is less than 13 mm, the spark might be generated even if the coil is malfunctioning.
OK or NG
OK >> GO TO 10.
NG >> GO TO 7.
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.
OK or NG
OK >> GO TO 8.
NG >> Check ignition coil, power transistor and their circuits. Refer to EC-691, "
IGNITION SIGNAL" . Spark should be generated.
PBIB2697E
PBIB2325E
Spark should be generated.
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
EC-355
[VQ35DE]
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Revision: 2007 April2007 M35/M45
8. 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 EM-45, "
SPARK PLUG (PLATI-
NUM-TIPPED TYPE)" .
NG >> 1. Repair or clean spark plug.
2. GO TO 9.
9. 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.
OK or NG
OK >>INSPECTION END
NG >> Replace spark plug(s) with standard type one(s). For spark plug type, refer to MA-20, "
Changing
Spark Plugs (Platinum-Tipped Type)" .
10. CHECK COMPRESSION PRESSURE
Check compression pressure. Refer to EM-102, "
CHECKING COMPRESSION PRESSURE" .
OK or NG
OK >> GO TO 11.
NG >> Check pistons, piston rings, valves, valve seats and cylinder head gaskets.
11 . CHECK FUEL PRESSURE
1. Install all removed parts.
2. Release fuel pressure to zero. Refer to EC-88, "
FUEL PRESSURE RELEASE" .
3. Install fuel pressure gauge and check fuel pressure. Refer to EC-89, "
FUEL PRESSURE CHECK" .
OK or NG
OK >> GO TO 13.
NG >> GO TO 12.
12. DETECT MALFUNCTIONING PART
Check the following.
Fuel pump and circuit (Refer to EC-675, "FUEL PUMP" .)
Fuel pressure regulator (Refer to EC-89, "FUEL PRESSURE CHECK" .)
Fuel lines (Refer to FL-3, "FUEL SYSTEM" .)
Fuel filter for clogging
>> Repair or replace.
SEF156I
Spark should be generated.
At idling: Approximately 350 kPa (3.57 kg/cm
2 , 51 psi)
EC-358
[VQ35DE]
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
Revision: 2007 April2007 M35/M45
16. REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace malfunctioning air fuel ratio (A/F) sensor 1.
CAUTION:
Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>>INSPECTION END
17. CHECK MASS AIR FLOW SENSOR
With CONSULT-II
1. Install all removed parts.
2. Start engine and warm it up to normal operating temperature.
3. Check mass air flow sensor signal in “DATA MONITOR” mode with CONSULT-II.
With GST
1. Install all removed parts.
2. Start engine and warm it up to normal operating temperature.
3. Check mass air flow sensor signal in Service $01 with GST.
OK or NG
OK >> GO TO 18.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
ground. Refer to EC-193, "
DTC P0101 MAF SENSOR" .
18. CHECK SYMPTOM MATRIX CHART
Check items on the rough idle symptom in EC-99, "
Symptom Matrix Chart" .
OK or NG
OK >> GO TO 19.
NG >> Repair or replace.
19. ERASE THE 1ST TRIP DTC
Some tests may cause a 1st trip DTC to be set.
Erase the 1st trip DTC from the ECM memory after performing the tests. Refer to EC-68, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
>> GO TO 20.
20. CHECK INTERMITTENT INCIDENT
Refer to EC-153, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END 2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm
2.0 - 6.0 g·m/sec: at idling
7.0 - 20.0 g·m/sec: at 2,500 rpm
EC-380
[VQ35DE]
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
Revision: 2007 April2007 M35/M45
DTC P0420, P0430 THREE WAY CATALYST FUNCTIONPFP:20905
On Board Diagnosis LogicNBS004ZC
The ECM monitors the switching frequency ratio of air fuel ratio (A/F) sensor 1 and heated oxygen sensor 2.
A three way catalyst 1 with high oxygen storage capacity will indicate a low switching frequency of heated oxy-
gen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will
increase.
When the frequency ratio of A/F sensor 1 and heated oxygen sensor 2 approaches a specified limit value, the
three way catalyst 1 malfunction is diagnosed.
DTC Confirmation ProcedureNBS004ZD
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
Do not hold engine speed for more than the specified minutes below.
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70°C
(158°F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70°C (158°F).
7. Open engine hood.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0420
0420
(Bank 1)
Catalyst system effi-
ciency below threshold
Three way catalyst (manifold) does not oper-
ate properly.
Three way catalyst (manifold) does not have
enough oxygen storage capacity.
Three way catalyst (manifold)
Exhaust tube
Intake air leaks
Fuel injector
Fuel injector leaks
Spark plug
Improper ignition timing P0430
0430
(Bank 2)
PBIB1923E
SEF189Y
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
EC-383
[VQ35DE]
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Revision: 2007 April2007 M35/M45
5. CHECK FUEL INJECTORS
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-II or tester.
Refer to Wiring Diagram for fuel Injectors, EC-670, "
Wiring Dia-
gram" .
OK or NG
OK >> GO TO 6.
NG >> Perform EC-671, "
Diagnostic Procedure" .
6. 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 (1) in IPDM E/R (2) to release fuel pres-
sure.
NOTE:
Do not use CONSULT-II to release fuel pressure, or fuel pres-
sure 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 electri-
cal 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
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 por-
tion.
CAUTION:
Do not approach to the spark plug and the ignition coil
within 50cm. 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 is taken.
NOTE:
When the gap is less than 13 mm, the spark might be generated even if the coil is malfunctioning.
OK or NG
OK >> GO TO 10.
NG >> GO TO 7.Voltage: Battery voltage
PBIB1172E
Spark should be generated.
PBIB2697E
PBIB2325E
EC-384
[VQ35DE]
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
Revision: 2007 April2007 M35/M45
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.
OK or NG
OK >> GO TO 8.
NG >> Check ignition coil, power transistor and their circuits. Refer to EC-691, "
IGNITION SIGNAL" .
8. 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 MA-20, "
Changing Spark Plugs
(Platinum-Tipped Type)" .
NG >> 1. Repair or clean spark plug.
2. GO TO 9.
9. 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.
OK or NG
OK >>INSPECTION END
NG >> Replace spark plug(s) with standard type one(s). For spark plug type, refer to MA-20, "
Changing
Spark Plugs (Platinum-Tipped Type)" .
10. CHECK FUEL INJECTOR
1. Turn ignition switch OFF.
2. Remove fuel injector assembly.
Refer to EM-47, "
FUEL INJECTOR AND FUEL TUBE" .
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.
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.Spark should be generated.
SEF156I
Spark should be generated.