Infiniti M35/M45 Y50. Manual - part 404

BASIC SERVICE PROCEDURE

EC-89

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 Without CONSULT-II

1.

Remove fuel pump fuse (1) located in IPDM E/R (2).

2.

Start engine.

3.

After engine stalls, crank it two or three times to release all fuel
pressure.

4.

Turn ignition switch OFF.

5.

Reinstall fuel pump fuse after servicing fuel system.

FUEL PRESSURE CHECK

CAUTION:

Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.

NOTE:

●

Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel
pressure cannot be completely released because Y50 models do not have fuel return system.

●

Use Fuel Pressure Gauge Kit (J-44321) to check fuel pressure.

1.

Release fuel pressure to zero. Refer to 

EC-88, "FUEL PRESSURE RELEASE"

 .

2.

Install the inline fuel quick disconnected fitting between fuel
damper and fuel injector tube.

3.

Connect the fuel pressure test gauge (quick connector adapter
hose) to the inline fuel quick disconnected fitting.

4.

Turn ignition switch ON and check for fuel leakage.

5.

Start engine and check for fuel leakage.

6.

Read the indication of fuel pressure gauge.

7.

If result is unsatisfactory, go to next step.

8.

Check the following.

●

Fuel hoses and fuel tubes for clogging

●

Fuel filter for clogging

●

Fuel pump

●

Fuel pressure regulator for clogging

If OK, replace fuel pressure regulator.
If NG, repair or replace.

PBIB2697E

At idling:

Approximately 350 kPa (3.57 kg/cm

2

 , 51 psi)

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TROUBLE DIAGNOSIS

TROUBLE DIAGNOSIS

PFP:00004

Trouble Diagnosis Introduction

NBS004SY

INTRODUCTION

The engine has an ECM to control major systems such as fuel con-
trol, ignition control, idle air control system, etc. The ECM accepts
input signals from sensors and instantly drives actuators. It is essen-
tial that both input and output signals are proper and stable. At the
same time, it is important that there are no malfunctions such as vac-
uum leaks, fouled spark plugs, or other malfunctions with the engine.

It is much more difficult to diagnose an incident that occurs intermit-
tently rather than continuously. Most intermittent incidents are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.

A visual check only may not find the cause of the incidents. A road
test with CONSULT-II (or GST) or a circuit tester connected should
be performed. Follow the Work Flow on 

EC-91

 .

Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such incidents, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A Diagnostic Worksheet like the example
on 

EC-95

   should be used.

Start your diagnosis by looking for conventional malfunctions first.
This will help troubleshoot driveability malfunctions on an electroni-
cally controlled engine vehicle.

MEF036D

SEF233G

SEF234G

TROUBLE DIAGNOSIS

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WORK FLOW
Overall Sequence

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TROUBLE DIAGNOSIS

Detailed Flow

1. 

GET INFORMATION FOR SYMPTOM

Get the detailed information from the customer about the symptom (the condition and the environment when
the incident/malfunction occurred) using the 

EC-94, "DIAGNOSTIC WORKSHEET"

 .

>> GO TO 2.

2. 

CHECK DTC*

1

1.

Check DTC*

1

 .

2.

Perform the following procedure if DTC*

1

  is displayed.

–

Record DTC*

1

  and freeze frame data*

2

 . (Print them out with CONSULT-II or GST.)

–

Erase DTC*

1

 . (Refer to 

EC-68, "HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION"

.)

–

Study the relationship between the cause detected by DTC*

1

  and the symptom described by the cus-

tomer. (Symptom Matrix Chart is useful. Refer to 

EC-99, "Symptom Matrix Chart"

 .)

3.

Check related service bulletins for information.

Is any symptom described and any DTC detected?

Symptom is described, DTC*

1

  is displayed>>GO TO 3.

Symptom is described, DTC*

1

  is not displayed>>GO TO 4.

Symptom is not described, DTC*

1

  is displayed>>GO TO 5.

3. 

CONFIRM THE SYMPTOM

Try to confirm the symptom described by the customer (except MIL ON).
DIAGNOSIS WORK SHEET is useful to verify the incident.
Connect CONSULT-II to the vehicle in “DATA MONITOR (AUTO TRIG)” mode and check real time diagnosis
results.
Verify relation between the symptom and the condition when the symptom is detected.

>> GO TO 5.

4. 

CONFIRM THE SYMPTOM

Try to confirm the symptom described by the customer.
DIAGNOSIS WORK SHEET is useful to verify the incident.
Connect CONSULT-II to the vehicle in “DATA MONITOR (AUTO TRIG)” mode and check real time diagnosis
results.
Verify relation between the symptom and the condition when the symptom is detected.

>> GO TO 6.