Infiniti G20 (P11). Manual — part 162

7

CHECK TARGET IDLE SPEED

With CONSULT-II

1. Read idle speed in “DATA MONITOR” mode with CONSULT-II.

SEF058Y

M/T: 800

±

50 rpm

A/T: 800

±

50 rpm (in “P” or “N” position)

Without CONSULT-II

1. Check idle speed.

M/T: 800

±

50 rpm

A/T: 800

±

50 rpm (in “P” or “N” position)

OK or NG

OK (With CONSULT-II)

©

GO TO 9.

OK (Without CONSULT-
II)

©

GO TO 10.

NG

©

GO TO 8.

8

DETECT MALFUNCTIONING PART

Check the following.

I

Check IACV-AAC valve and replace if necessary. Refer to EC-436.

I

Check IACV-AAC valve harness and repair if necessary. Refer to EC-436.

I

Check ECM function by substituting another known-good ECM.
(ECM may be the cause of a problem, but this is rarely the case.)

With
CONSULT-II

©

GO TO 9.

Without
CONSULT-II

©

GO TO 10.

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HA

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IDX

BASIC SERVICE PROCEDURE

Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (Cont’d)

EC-59

9

CHECK HEATED OXYGEN SENSOR 1 (FRONT) SIGNAL

With CONSULT-II

1. See “HO2S1 MNTR (B1)” in “DATA MONITOR” mode.
2. Maintaining engine at 2,000 rpm under no-load (engine is warmed up to normal operating temperature.), check that the

monitor fluctuates between “LEAN” and “RICH” more than 5 times during 10 seconds.

SEF820Y

1 time: RICH

→

LEAN

→

RICH

2 times: RICH

→

LEAN

→

RICH

→

LEAN

→

RICH

OK or NG

OK

©

INSPECTION END

NG (Monitor does not
fluctuate.)

©

GO TO 13.

NG (Monitor fluctuates
less than 5 times.)

©

GO TO 11.

10

CHECK HEATED OXYGEN SENSOR 1 (FRONT) SIGNAL

Without CONSULT-II

1. Set voltmeter probe between ECM terminal 62 and ground.
2. Make sure that the voltage fluctuates between 0 - 0.3V and 0.6 - 1.0V more than 5 times during 10 seconds at 2,000

rpm.
1 time: 0 - 0.3V

→

0.6 - 1.0V

→

0 - 0.3V

2 times: 0 - 0.3V

→

0.6 - 1.0V

→

0 - 0.3V

→

0.6 - 1.0V

→

0 - 0.3V

OK or NG

OK

©

INSPECTION END

NG (Voltage does not
fluctuate.)

©

GO TO 13.

NG (Voltage fluctuates
less than 5 times.)

©

GO TO 11.

BASIC SERVICE PROCEDURE

Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (Cont’d)

EC-60

11

CHECK HEATED OXYGEN SENSOR 1 (FRONT) SIGNAL

With CONSULT-II

1. Stop engine.
2. Replace heated oxygen sensor 1 (front).
3. Start engine and warm it up to normal operating temperature.
4. Run engine at approx. 2,000 rpm for approx. 2 minutes under no-load.
5. See “HO2S1 MNTR (B1)” in “DATA MONITOR” mode.
6. Maintaining engine at 2,000 rpm under no-load (engine is warmed up to normal operating temperature.), check that the

monitor fluctuates between “LEAN” and “RICH” more than 5 times during 10 seconds.
1 time: RICH

→

LEAN

→

RICH

2 times: RICH

→

LEAN

→

RICH

→

LEAN

→

RICH

Without CONSULT-II

1. Stop engine.
2. Replace heated oxygen sensor 1 (front).
3. Start engine and warm it up to normal operating temperature.
4. Run engine at approx. 2,000 rpm for approx. 2 minutes under no-load.
5. Set voltmeter probe between ECM terminal 62 and ground.
6. Make sure that the voltage fluctuates between 0 - 0.3V and 0.6 - 1.0V more than 5 times during 10 seconds at 2,000

rpm.
1 time: 0 - 0.3V

→

0.6 - 1.0V

→

0 - 0.3V

2 times: 0 - 0.3V

→

0.6 - 1.0V

→

0 - 0.3V

→

0.6 - 1.0V

→

0 - 0.3V

OK or NG

OK

©

INSPECTION END

NG

©

GO TO 12.

12

DETECT MALFUNCTIONING PART

Check the following.

I

Check fuel pressure regulator. Refer to EC-51.

I

Check mass air flow sensor and its circuit. Refer to EC-154.

I

Check injector and its circuit. Refer to EC-596.
Clean or replace if necessary.

I

Check engine coolant temperature sensor and its circuit. Refer to EC-171.

I

Check ECM function by substituting another known-good ECM.
(ECM may be the cause of a problem, but this is rarely the case.)

©

GO TO 6.

13

CHECK HEATED OXYGEN SENSOR 1 (FRONT) HARNESS

1. Turn off engine and disconnect battery ground cable.
2. Disconnect ECM harness connector.
3. Disconnect heated oxygen sensor 1 (front) harness connector.
4. Check harness continuity between ECM terminal 62 and heated oxygen sensor 1 (front) harness connector terminal 2.

Refer to Wiring Diagram, EC-199.

Continuity should exist.

OK or NG

OK

©

GO TO 15.

NG

©

GO TO 14.

14

REPAIR OR REPLACE

Repair or replace harness between ECM and heated oxygen sensor 1 (front).

©

GO TO 6.

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IDX

BASIC SERVICE PROCEDURE

Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (Cont’d)

EC-61

15

PREPARATION FOR “CO” % CHECK

With CONSULT-II

1. Reconnect ECM harness connector.
2. Turn ignition switch “ON”.
3. Select “ENG COOLANT TEMP” in “ACTIVE TEST” mode.
4. Set “ENG COOLANT TEMP” to 5°C (41°F) by touching “DWN” and “Qd”.

SEF172Y

Without CONSULT-II

1. Disconnect ECM harness connector.
2. Disconnect engine coolant temperature sensor harness connector.
3. Connect a resistor (4.4 k

Ω

) between terminals of engine coolant temperature sensor harness connector.

SEF982UA

©

GO TO 16.

BASIC SERVICE PROCEDURE

Idle Speed/Ignition Timing/Idle Mixture Ratio Adjustment (Cont’d)

EC-62