Nissan Frontier D40. Manual - part 488

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

EC-643

< COMPONENT DIAGNOSIS >

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2.

Listen for an exhaust gas leak before three way catalyst (manifold).

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace.

2.

CHECK FOR INTAKE AIR LEAK

Listen for an intake air leak after the mass air flow sensor.

OK or NG

OK

>> GO TO 3.

NG

>>  Repair or replace.

3.

CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect corresponding A/F sensor 1 harness connector.

3.

Disconnect ECM harness connector.

4.

Check harness continuity between A/F sensor 1 terminal and ECM terminal as follows.
Refer to Wiring Diagram.

5.

Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.

6.

Also check harness for short to power.

PBIB1216E

Bank 1

A/F sensor 1 terminal

ECM terminal

1

35

2

56

Bank 2

1

16

2

75

Continuity should exist.

Bank 1

Bank 2

A/F sensor 1 terminal

ECM terminal

A/F sensor 1 terminal

ECM terminal

1

35

1

16

2

56

2

75

Continuity should not exist.

BBIA0544E

EC-644

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[VQ40DE]

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

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 FUEL PRESSURE

1.

Release fuel pressure to zero. Refer to 

EC-954, "Fuel Pressure Check"

.

2.

Install fuel pressure gauge and check fuel pressure. Refer to 

EC-954, "Fuel Pressure Check"

.

OK or NG

OK (With CONSULT-III)>>GO TO 6.
OK (Without CONSULT-III)>>GO TO 7.
NG

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART

Check the following.
• Fuel pump and circuit (Refer to, 

EC-862, "Description"

.)

• Fuel pressure regulator (Refer to 

EC-954, "Fuel Pressure Check"

.)

>> Repair or replace.

6.

CHECK MASS AIR FLOW SENSOR

 With CONSULT-III

1.

Install all removed parts.

2.

Check “MASS AIR FLOW” in “DATA MONITOR” mode with CONSULT-III.

OK or NG

OK

>> GO TO 8.

NG

>> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or

ground. Refer to 

EC-565, "Component Description"

.

7.

CHECK MASS AIR FLOW SENSOR

 With GST

1.

Install all removed parts.

2.

Check mass air flow sensor signal in Service $01 with GST.

OK or NG

OK (P0172)>>GO TO 9.
OK (P0175)>>GO TO 11.
NG

>> Check connectors for rusted terminals or loose connections in the mass air flow sensor circuit or

ground. Refer to 

EC-565, "Component Description"

.

8.

CHECK FUNCTION OF FUEL INJECTOR

 With CONSULT-III

1.

Start engine.

2.

Perform “POWER BALANCE” in “ACTIVE TEST” mode with CONSULT-III.

3.

Check that each circuit produces a momentary engine speed drop.

OK or NG

OK

>> GO TO 12.

NG

>> Perform trouble diagnosis for FUEL INJECTOR, refer to 

EC-858, "Component Description"

.

At idling: 350 kPa (3.57 kg/cm

2

, 51 psi)

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

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

EC-645

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9.

CHECK FUNCTION OF FUEL INJECTOR-I

 Without CONSULT-III

1.

Stop engine.

2.

Disconnect harness connector F44 (3), F201 (1)

3.

Turn ignition switch ON.

4.

Check voltage between harness connector F44 terminal 3 and
ground with CONSULT-III or tester.

5.

Turn ignition switch OFF.

6.

Disconnect ECM harness connector.

7.

Check harness continuity between harness connector F44 and
ECM as follows.
Refer to Wiring Diagram.

8.

Also check harness for short to ground and short to power.

OK or NG

OK

>> GO TO 10.

NG

>> Perform trouble diagnosis for FUEL INJECTOR, refer to 

EC-858, "Component Description"

.

10.

CHECK FUNCTION OF FUEL INJECTOR-II

Provide battery voltage between harness connector F201 as follows
and then interrupt it. Listen to each fuel injector operating sound.

OK or NG

OK

>> GO TO 12.

NG

>> Perform trouble diagnosis for FUEL INJECTOR, refer to 

EC-858, "Component Description"

.

11.

CHECK FUNCTION OF FUEL INJECTOR

2

: Vacuum tank

: Front

AWBIA0686ZZ

Voltage: Battery voltage

Cylinder

Harness connector F44 

terminal

ECM terminal

1

2

23

3

1

22

5

4

21

Continuity should exist.

PBIB2633E

Cylinder

Harness connector F201 terminal

(+)

(–)

1

3

2

3

3

1

5

3

4

Operating sound should exist.

PBIB2634E

EC-646

< COMPONENT DIAGNOSIS >

[VQ40DE]

P0172, P0175 FUEL INJECTION SYSTEM FUNCTION

1.

Start engine.

2.

Listen to fuel injectors No.2, No.4, No.6 operating sound.

OK or NG

OK

>> GO TO 12.

NG

>> Perform trouble diagnosis for FUEL INJECTOR, refer to

EC-858, "Component Description"

.

12.

CHECK FUEL INJECTOR

1.

Remove fuel injector assembly. Refer to 

EM-159, "Removal and Installation"

.

Keep fuel hose and all fuel injectors connected to fuel tube.

2.

Confirm that the engine is cooled down and there are no fire hazards near the vehicle.

3.

Disconnect all fuel injector harness connectors.

4.

Disconnect all ignition coil harness connectors.

5.

Prepare pans or saucers under each fuel injector.

6.

Crank engine for about 3 seconds.
Make that sure fuel does not drip from fuel injector.

OK or NG

OK (Does not drip.)>>GO TO 13.
NG (Drips.)>>Replace the fuel injectors from which fuel is dripping. Always replace O-ring with new one.

13.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-42, "Work Flow"

.

>> INSPECTION END

Clicking noise should exist.

PBIB1986E