Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 96

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

6E–379

EXCESSIVE BLACK SMOKE

Step

Action

Value(s)

Yes

No

1

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

—

Go to Step 2

Go to On Board 

Diagnostic 

(OBD) System 

Check

2

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

3

Was a visually/physical check performed?

—

Go to Step 4

Go to Visual / 

physical Check.

4

Is the customer using the incorrect fuel type? 

Diesel fuel 

only

Replace with 

diesel fuel

Go to Step 5

5

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 6

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

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

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 22

Go to Step 9

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

6E–380

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

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

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

12

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

—

Go to Step 13

Go to Step 22

13

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

—

Verify repair

—

14

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

“Run”. 

2. Monitor the following parameters in the data

display. 

• “Desired Injection Quantity” & “Injection Quantity” 

• “Desired Injection Start” &  “Actual Injection Start”

Are the large gap or unstable parameter displayed
between “Desired” and “Actual”?

—

Go to Step 21

Go to Step 15

15

Using the vacuum pump and check the EGR valve (if
equipped) operation for the following condition through
the small window. 

• Restrict shaft movement. Check for objects sticking

the shaft, broken diaphragm or excessive carbon
deposit. 

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

—

Verify repair

Go to Step 16

Step

Action

Value(s)

Yes

No

                  When idling or part-throttle                                            When accelerated

                                                                                     

                                                                                   

High

Desired

Low

Time

    Actual

High

Low

Desired

    Actual

Time

Vacuum Pump

Small Window

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

6E–381

16

Using the vacuum pump and check the exhaust
throttle valve (if equipped) operation for the following
condition. 

• Restrict shaft movement. Check for objects sticking

the shaft, broken diaphragm or excessive carbon
deposit. 

Was a problem found? 

—

Verify repair

Go to Step 17

17

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 18

18

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 19

Step

Action

Value(s)

Yes

No

1

st

 Stage

2

nd

 Stage

4JA1-TC

19.5 - 20.5 Mpa

(199 -209 kg/cm

2

)

34.0 - 35.5 Mpa

(347 - 362 kg/cm

2

)

4JH1-TC

20.0 - 21.0 Mpa

(204 -214 kg/cm

2

)

34.3 - 35.8 Mpa

(350 - 365 kg/cm

2

)

6E–382

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

19

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/

cm

2

)

Verify repair

Go to Step 20

20

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 21

Adjust and 

verify repair

21

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 22

22

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 23

23

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 24

Go to Step 25

Step

Action

Value(s)

Yes

No