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Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 176

6E–308

4JH1 ENGINE DRIVEABILITY AND EMISSIONS

1. Using the Tech 2, ignition “On”.

2. Monitor the “Glow Time Relay” in the data display

and then, does the supply voltage correctly supply
to the glow plug?

—

Go to Step 11

Repair voltage

supply circuit

and verify repair

Check the glow plugs for continuity.
If a problem is found, repair as necessary.
Was a problem found?

—

Verify repair

Go to Step 12

Check the exhaust system for a possible restriction.

• Damaged or collapsed pipes or catalytic converter.

• Internal muffler failure.
If a problem is found, repair as necessary.
Was a problem found?

—

Verify repair

Go to Step 13

Visually/physically inspect for the following conditions.

• Restrict fuel supply system. Check for a pinched

fuel hose/pipe.

• Check for a condition that causes fuel waxing or

icing, such as the customer is using an incorrect
fuel type in winter season or water mixed with the
fuel.

If a problem is found, repair as necessary.
Was a problem found?

—

Verify repair

Go to Step 14

Replace the fuel filter.
Was the problem solved?

—

Verify repair

Go to Step 15

Step

Action

Value(s)

Yes

4JH1 ENGINE DRIVEABILITY AND EMISSIONS

6E–309

Remove the eye bolt with gauze filter from the
injection pump and check for the following conditions.

• Objects blocking at the gauze filter. Check for a

condition that causes contaminated fuel, such as
the customer is using an aftermarket fuel filter or
extended maintenance interval.

• Check for a condition that causes fuel waxing or

icing, such as the customer is using an incorrect
fuel type in winter season or water mixed with the
fuel.

If a problem is found, repair as necessary.
Was the problem found?

—

Replace the eye

bolt with gauze

filter and verify

repair

Go to Step 16

Remove the injection nozzles from the engine and
check for the following conditions.

• Improper splay condition.

• Operating pressure is incorrect.
If a problem is found, repair as necessary.
Was the problem found?

—

Replace the

injection nozzle

and verify repair

Go to Step 17

Check the engine compression pressure for each
cylinders.
If a problem is found, repair as necessary.
Was the problem found?

More than 30

Mpa (31.0 kg/

)

Verify repair

Go to Step 18

Step

Action

Value(s)

Yes

Stage

20.0 - 21.0 Mpa

(204 - 214 kg/cm

)

34.3 - 35.8 Mpa

(350 - 365 kg/cm

)

6E–310

4JH1 ENGINE DRIVEABILITY AND EMISSIONS

Check the inlet/exhaust valve clearance for each
valves.
Are the valve clearances within the specified value?

0.4mm at cold

(In/Ex)

Go to Step 19

Adjust and

verify repair

1. Review all diagnostic procedures within this table.

2. If all procedures have been completed and no

malfunctions have been found, review/inspect the
following:

• Visual/physical inspection

• Tech 2 data

• All electrical connections within a suspected circuit

and/or system

Was a problem found?

—

Verify repair

Go to Step 20

Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the “SPS (Service Programming System)”.
Was the problem solved?

—

Verify repair

Go to Step 21

Substitute a known good ECM and recheck.
Was the problem solved?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobiliser system
(if equipped) must be linked to the ECM. Refer to
section 11 “Immobiliser System-ECM replacement” for
the ECM/Immobiliser linking procedure.

—

Go to Step 22

Go to Step 23

Replace the ECM.
Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobiliser system
(if equipped) must be linked to the ECM. Refer to
section 11 “Immobiliser System-ECM replacement” for
the ECM/Immobiliser linking procedure.

—

Verify repair

—

Replace the injection pump assembly.
Is the action complete?

—

Verify repair

—

Step

Action

Value(s)

Yes

4JH1 ENGINE DRIVEABILITY AND EMISSIONS

6E–311

ROUGH, UNSTABLE, OR INCORRECT IDLE, STALLING SYMPTOM

DEFINITIONS: Engine runs unevenly at idle. If severe,
the engine or vehicle may shake. Engine idle speed may
vary in RPM. Either condition may be severe enough to
stall the engine.

time

rpm

Rough Idle

Stall

Step

Action

Value(s)

Yes

Was the “On-Board Diagnostic (OBD) System Check”
performed?

—

Go to Step 2

Go to On Board

Diagnostic

(OBD) System

Check

1. Perform a bulletin search.

2. If a bulletin that addresses the symptom is found,

correct the condition as instructed in the bulletin.

Was a bulletin found that addresses the symptom?

—

Verify repair

Go to Step 3

Was a visually/physical check performed?

—

Go to Step 4

Go to Visual /

physical Check

Is the customer using the incorrect fuel type?

Diesel fuel

only

Replace with

diesel fuel

Go to Step 5

1. Check for incorrect idle speed. Ensure that the

following conditions are present.

• Engine fully warm.

• Accessories are “OFF”.

2. Using a Tech 2, monitor “Desired Engine Idle

Speed” and “Engine Speed”.

Is the “Engine Speed” within the specified values?

Desired

Engine Idle

Speed ± 25

rpm

Go to Step 7

Go to Step 6

Visually/physically inspect for the following conditions.

• Restrict air intake system. Check for a restricted air

filter element, or foreign objects blocking the air
intake system

• Check for objects blocking or excessive deposits in

the throttle bore and on the throttle plate

• Check for a condition that causes a large vacuum

leak, such as an incorrectly installed or faulty
crankcase ventilation hose.

• Restrict air intake system at the turbocharger.

Check for objects blocking the turbocharger
compressor wheel or turbine shaft sticking.

If a problem is found, repair as necessary.
Was a problem found?

—

Verify repair

Go to Step 7

Check the ECM & PSG grounds to verify that they are
clean and tight. Refer to the ECM wiring diagrams.
Was a problem found?

—

Verify repair

Go to Step 8

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