Content .. 92 93 94 95 ..

Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 94

4JA1-TC/4JH1-TC ENGINE DRIVEABILITY AND EMISSIONS

6E–371

Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?

—

Go to Step 21

Go to Step 31

Replace the MAF & IAT sensor assembly.
Is the action complete?

—

Verify repair

—

1. Using the Tech 2, ignition “On” and engine “Off”.

2. Monitor the “Pedal/Throttle Position” and “Idle

Switch” in the data display.

Does the Tech 2 indicate correct “Pedal/Throttle
Position” from 0% to 100% and correct “Idle Switch”
status depending on accelerator pedal operation?

—

Go to Step 27

Go to Step 23

1. Using the Tech 2, ignition “On” and engine “Off”.

2. Monitor the “Pedal/Throttle Position” and “Idle

Switch” in the data display.

3. Adjust the accelerator cable or TPS within 0% to

100%.

Was the problem solved?

—

Verify repair

Go to Step 24

Check the TPS harness for the following conditions.

• Check for poor connector connection.

• Check for misrouted harness.

• Check for any accessory parts which may cause

electric interference.

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

—

Verify repair

Go to Step 25

Substitute a known good TPS and recheck.
Was the problem solved?

—

Go to Step 26

Go to Step 31

Replace the TPS.
Is the action complete?

—

Verify repair

—

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 28

Step

Action

Value(s)

Yes

Stage

4JA1-TC

19.5 - 20.5 Mpa

(199 -209 kg/cm

)

34.0 - 35.5 Mpa

(347 - 362 kg/cm

)

4JH1-TC

20.0 - 21.0 Mpa

(204 -214 kg/cm

)

34.3 - 35.8 Mpa

(350 - 365 kg/cm

)

6E–372

4JA1-TC/4JH1-TC ENGINE DRIVEABILITY AND EMISSIONS

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 29

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 30

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 31

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 32

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 33

Go to Step 34

Step

Action

Value(s)

Yes

4JA1-TC/4JH1-TC ENGINE DRIVEABILITY AND EMISSIONS

6E–373

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

6E–374

4JA1-TC/4JH1-TC ENGINE DRIVEABILITY AND EMISSIONS

EXCESSIVE WHITE SMOKE

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

Check the engine coolant consumption to verify that it
leaks to combustion chamber or exhaust through the
gasket.
Was a problem found?

—

Verify repair

Go to Step 6

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 7

1. Using the Tech 2, display the ECT sensor and IAT

sensor value.

2. Check the displayed value.

Does the Tech 2 indicate correct temperature
depending on engine condition?
If a problem is found, repair as necessary.
Was the problem found?

—

Verify repair

Go to Step 8

1. Using the Tech 2, display the FT sensor value.

2. Check the displayed value.

Does the Tech 2 indicate correct temperature
depending on engine condition?
If a problem is found, repair as necessary.
Was the problem found?

—

Go to Step 30

Go to Step 9

1. Using the Tech 2, ignition “On” and engine “Run”.

2. Monitor the “Mass Air Flow” in the data display.

Does the Tech 2 indicate correct “Mass Air Flow”
depending on accelerator pedal operation?

—

Go to Step 14

Go to Step 10

Remove the MAF & IAT sensor assembly and check
for the following conditions.

• Objects blocking at the MAF sensor element.
If a problem is found, repair as necessary.
Was the problem found?

—

Verify repair

Go to Step 11

Check the MAF sensor harness for the following
conditions.

• Check for poor connector connection.

• Check for misrouted harness.

• Check for any accessory parts which may cause

electric interference.

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

—

Verify repair

Go to Step 12

Content .. 92 93 94 95 ..