Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 257

ENGINE DRIVEABILITY AND EMISSIONS

6E–269

SPARK PLUGS

Location
Installed on the left-hand side of cylinder head.

Removal Procedure

1. Disconnect the negative battery cable

2. Remove the spark plug cable.

3. Remove the spark plug.

Inspection

1. Check the insulator for cracks. Replace the spark

plug if cracks are present.

2. Check the electrode condition and replace the spark

plug if necessary.

If the spark plug electrodes and insulators are fouled
with carbon or oil, the engine will not operate efficiently.
There are a number of possible causes:

• Fuel mixture is too rich.

• Oil in the combustion chamber.

• The spark plug gap is not set correctly.
If spark plug fouling is excessive, check the fuel and al
system for possible causes of trouble. If fuel and al
system are normal, install spark plugs of a higher heat
range which have the same physical dimensions as the
original equipment spark plugs.
The following symptoms are characteristics of spark
plugs that are running too hot:

• Fuel mixture is too lean.

• Heat range is incorrect.

If vehicle usage does not conform to normal driving
conditions, a more suitable spark plug may be
substituted.
If fuel and al system are normal, in most cases of this
sort, the problem can be corrected by using a colder
type spark plug with the same physical dimensions as
the original equipment spark plug.

3. Check the gaskets for damage and replace if

necessary.

4. Measure the spark plug gap. The specification is 1.0

to 1.1mm (0.039 to 0.043").

5. Adjust the spark gap by bending the grounded

electrode.

6E–270

ENGINE DRIVEABILITY AND EMISSIONS

Installation

1. Tighten the spark plug to the 25N·m (2.5kgf·m).

2. Push the spark plug cable in until it snaps in.

Installation Procedure

1. Install the spark plug to the cylinder head.

2. Tighten the spark plug with specified tightening

torque.

Tightening Torque

• Bolt: 25N·m (2.5kgf·m)

3. Connect the spark plug cable to the spark plug.

4. Connect the negative battery cable.

NOTE: Verify any DTCs (diagnosis Trouble Code) are
not stored after replacement.
Verify proper connection of spark plug cables for each
cylinders.

SPARK PLUG CABLES

The cable contains a synthetic conductor which is easily
damaged. Never stretch or kink the cable. Disconnect
the cable from spark plug and the ignition coil.
The original equipment cables and the ignition coil are
marked to show correct location of the cables. If spark
plug cables or the ignition coil are replaced previously,
before cables are removed from the ignition coil, mark
the cables and the coil so they can be reconnected in
the same position.

Inspection 
NOTE: Never puncture the spark plug cable’s insulation
with a needle or the pointed end of a probe into the
cable. An increase in resistance would be created which
would cause the cable to become defective.

1. If the cable has broken or cracked insulation, it must

be replaced.

2. If the terminals are corroded or loose, the cable

must be replaced.

3. Check that the cable resistance does not exceed

specified value.
#1 cylinder: 3.50k

Ω -  5.24kΩ

#2 cylinder: 2.89k

Ω - 4.33kΩ

#3 cylinder: 2.49k

Ω - 3.73kΩ

#4 cylinder: 2.22k

Ω - 3.32kΩ

ENGINE DRIVEABILITY AND EMISSIONS

6E–271

SPECIAL SERVICE TOOLS

ILLUSTRATION

TOOL NO.

TOLL NAME

5-8840-0285-0

(J 39200)

High Impedance

Multimeter

(Digital Voltmeter -DVM)

(1) PCMCIA Card

(2) RS232 Loop Back 

Connector

(3) SAE 16/19 Adapter

(4) DLC Cable

(5) TECH 2

5-8840-0385-0

(J 35616-A/BT-8637)

Connector Test Adapter Kit

5-8840-0378-0

(J34730-E)

Port Fuel Injection 

Diagnostic Kit

Breaker Box

5-8840-2589-0

Injector Adapter Cable

HECED-WE-0321

You are requested to order this manual using the 
manual number that is shown above.

All rights reserved, This manual may not be reproduced 
in whole or in part, without the permission in writing of 
ISUZU MOTORS LIMITED.

Issued by

ISUZU MOTORS LIMITED

INTERNATIONAL SERVICE DEPARTMENT

Tokyo, Japan

First edition Oct., 2002