Page 359 of 720

DTC P0197, P0198 EOT SENSOR
EC-359
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2. CHECK EOT SENSOR POWER SUPPLY CIRCUIT
1. Disconnect engine oil temperature (EOT) sensor (1) harness
connector.
2. Turn ignition switch ON.
3. Check voltage between EOT sensor terminal 1 and ground with
CONSULT-III or tester.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
3. CHECK EOT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 84 and ECT sensor terminal 2.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK ENGINE OIL TEMPERATURE SENSOR
Refer to EC-360, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace engine oil temperature sensor.
5. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
: Vehicle front
PBIB3562E
Voltage: Approximately 5V
PBIB0080E
Continuity should exist.
Page 360 of 720
EC-360
DTC P0197, P0198 EOT SENSOR
Revision: 2006 November2007 350Z
Component InspectionNBS006TV
ENGINE OIL TEMPERATURE SENSOR
1. Check resistance between engine oil temperature sensor termi-
nals 1 and 2 as shown in the figure.
2. If NG, replace engine oil temperature sensor.
Removal and InstallationNBS006TW
ENGINE OIL TEMPERATURE SENSOR
Refer to EM-26, "OIL PAN AND OIL STRAINER" .
PBIB2005E
Temperature°C (°F) Resistance kΩ
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
SEF012P
Page 362 of 720
EC-362
DTC P0222, P0223, P2132, P2133 TP SENSOR
Revision: 2006 November2007 350Z
DTC Confirmation ProcedureNBS0007P
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.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
WITH CONSULT-III
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-367, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Page 372 of 720

EC-372
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
Revision: 2006 November2007 350Z
DTC Confirmation ProcedureNBS0007V
CAUTION:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws when driv-
ing.
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-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Restart engine and let it idle for about 15 minutes.
4. Check 1st trip DTC.
5. If 1st trip DTC is detected, go to EC-372, "
Diagnostic Procedure" .
NOTE:
If 1st trip DTC is not detected during above procedure, performing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for a certain
time. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con-
ditions should be satisfied at the same time.
The time to driving varies according to the engine speed in the freeze frame data.
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnostic ProcedureNBS0007W
1. CHECK FOR INTAKE AIR LEAK AND PCV HOSE
1. Start engine and run it at idle speed.
2. Listen for the sound of the intake air leak.
3. Check PCV hose connection.
OK or NG
OK >> GO TO 2.
NG >> Discover air leak location and repair.
Engine speed Engine speed in the freeze frame data ± 400 rpm
Vehicle speed Vehicle speed in the freeze frame data ± 10 km/h (6 MPH)
Engine coolant temperature
(T) conditionWhen the freeze frame data shows lower than 70 °C (158 °F),
T should be lower than 70 °C (158 °F).
When the freeze frame data shows higher than or equal to 70 °C (158 °F),
T should be higher than or equal to 70 °C (158 °F).
Engine speed Time
Around 1,000 rpm Approximately 10 minutes
Around 2,000 rpm Approximately 5 minutes
More than 3,000 rpm Approximately 3.5 minutes
Page 373 of 720

DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
EC-373
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2. CHECK FOR EXHAUST SYSTEM CLOGGING
Stop engine and visually check exhaust tube, three way catalyst and muffler for dents.
OK or NG
OK (With CONSULT-III)>>GO TO 3.
OK (Without CONSULT-III)>>GO TO 4.
NG >> Repair or replace it.
3. PERFORM POWER BALANCE TEST
With CONSULT-III
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode.
2. Is there any cylinder which does not produce a momentary engine speed drop?
Ye s o r N o
Ye s > > G O T O 4 .
No >> GO TO 9.
4. CHECK FUNCTION OF FUEL INJECTOR
With CONSULT-III
1. Start engine.
2. Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT-III.
3. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-III
1. Start engine and let it idle.
2. Listen to each fuel injector operating sound.
OK or NG
OK >> GO TO 5.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to
EC-686, "
FUEL INJECTOR" .
Clickng sound should be heard.
PBIB3332E
Page 374 of 720

EC-374
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
Revision: 2006 November2007 350Z
5. 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. Reconnect all harness connectors disconnected.
3. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
Do not use CONSULT-III to release fuel pressure, or fuel pres-
sure applies again during the following procedure.
4. Start engine.
5. After engine stalls, crank it two or three times to release all fuel
pressure.
6. Turn ignition switch OFF.
7. Remove all ignition coil harness connectors to avoid the electri-
cal discharge from the ignition coils.
8. Remove ignition coil and spark plug of the cylinder to be
checked.
9. Crank engine for 5 seconds or more 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
between the edge of the spark plug and grounded metal portion
as shown in the figure.
12. 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 9.
NG >> GO TO 6.
6. 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 7.
NG >> Check ignition coil, power transistor and their circuits. Refer to EC-698, "
IGNITION SIGNAL" . Spark should be generated.
PBIB2206E
PBIB2325E
Spark should be generated.
Page 375 of 720

DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
EC-375
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7. 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-18, "
Changing Spark Plugs
(Iridium-Tipped Type)" .
NG >> 1. Repair or clean spark plug.
2. GO TO 8.
8. 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-18, "
Changing
Spark Plugs (Iridium-Tipped Type)" .
9. CHECK COMPRESSION PRESSURE
Check compression pressure. Refer to EM-89, "
CHECKING COMPRESSION PRESSURE" .
OK or NG
OK >> GO TO 10.
NG >> Check pistons, piston rings, valves, valve seats and cylinder head gaskets.
10. CHECK FUEL PRESSURE
1. Install all removed parts.
2. Release fuel pressure to zero. Refer to EC-79, "
FUEL PRESSURE RELEASE" .
3. Install fuel pressure gauge and check fuel pressure. Refer to EC-80, "
FUEL PRESSURE CHECK" .
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . DETECT MALFUNCTIONING PART
Check the following.
Fuel pump and circuit (Refer to EC-691, "FUEL PUMP" .)
Fuel pressure regulator (Refer to EC-80, "FUEL PRESSURE CHECK" .)
Fuel lines (Refer tor FL-3, "Checking Fuel Lines" .)
Fuel filter for clogging
>> Repair or replace.
SEF156I
Spark should be generated.
At idle: Approximately 350 kPa (3.57 kg/cm
2 , 51 psi)
Page 378 of 720

EC-378
DTC P0300 - P0306 MULTIPLE CYLINDER MISFIRE, NO. 1 - 6 CYLINDER MIS-
FIRE
Revision: 2006 November2007 350Z
15. CHECK MASS AIR FLOW SENSOR
With CONSULT-III
1. Start engine and warm it up to normal temperature.
2. Check mass air flow sensor signal in “DATA MONITOR” mode with CONSULT-III.
With GST
1. Start engine and warm it up to normal temperature.
2. Check mass air flow sensor signal in Service $01 with GST.
OK or NG
OK >> GO TO 16.
NG >> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or
ground. Refer to EC-197, "
DTC P0101, P010B MAF SENSOR" .
16. CHECK SYMPTOM MATRIX CHART
Check items on the rough idle symptom in EC-90, "
Symptom Matrix Chart" .
OK or NG
OK >> GO TO 17.
NG >> Repair or replace.
17. 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-61, "
HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION" .
>> GO TO 18.
18. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
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