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Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 247

ENGINE DRIVEABILITY AND EMISSIONS

6E–229

1. Using a Tech 2, display the engine coolant

temperature and note the value.

2. Check the resistance of the engine coolant

temperature sensor.

Is the actual resistance near the resistance value in
the chart for the temperature that was noted?

—

Go to Step 8

Replace the

ECT sensor.

Verify repair

1. Using a Tech 2, display the MAP sensor value in

comparison with atmosphere temperature.

2. Check for a faulty, plugged, or incorrectly installed

MAP sensor.

Was the problem found?

—

Verify repair

Go to Step 9

Visually/physically inspect all spark plug high-tension
cables. Check for the following conditions:

• Verify that the resistance of all spark plug high-

tension cables are less than the specified value.

• Verify that the all spark plug high-tension cables are

correctly fitted to eliminate cross-fitting.

• Verify that the all spark plug high-tension cables are

not arcing to ground.
Spraying the spark plug high-tension cables with a
light mist of water may help locate an intermittent
problem.

Was a problem found?

#1 cyl. 4.4k

Ω

#2 cyl. 3.6k

Ω

#3 cyl. 3.1k

Ω

#4 cyl. 2.8k

Ω

Verify repair

Go to Step 10

Check for proper ignition voltage output with a spark
tester.
Was the problem found?

—

Verify repair

Go to Step 11

1. Remove the spark plugs and check for gas or oil

fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.

2. If spark plugs are fouled, the cause of fouling must

be determined before replacing the spark plugs.

Was a problem found?

—

Verify repair

Go to Step 12

Check for a loose ignition control module ground.
Was a problem found?

—

Verify repair

Go to Step 13

1. Check the ignition coil secondary resistance.

2. Replace the coil if it is greater than the specified

resistance.

Did the coil require replacement?

2.5k

Ω

Verify repair

Go to Step 14

Step

Action

Value(s)

Yes

Temperature (°C)

Resistance (

Ω) (Approximately)

-20

32040

9788

3516

1439

656

327

100

175

120

100

6E–230

ENGINE DRIVEABILITY AND EMISSIONS

Drain sample fuel, visual inspection.
Any suspecion about the fuel, such as discoloration,
particle, contamination, water, unusual smell, then
drain the fuel from fuel tank.
Replace the fuel from know vehicle source.
If any suspicion of alcohol contamination, completely
drain the fuel, replace by fuel from known vehicle
source.

—

Verify repair

Go to Step 15

Perform the procedure in Fuel System Pressure Test
to determine if there is a problem with fuel delivery.
Was a problem found?

—

Verify repair

Go to Step 16

1. Check the injector connectors.

2. If any of the connectors are connected at an

improper cylinder, connect as necessary.

Was a problem found?

—

Verify repair

Go to Step 17

Check for the following engine mechanical problems
(refer to Engine Mechanical):

• Low compression

• Leaking cylinder head gaskets

• Worn camshaft

• Camshaft drive belt slipped or stripped
Was a problem found?

—

Verify repair

Go to Step 18

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 19

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 20

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

—

Step

Action

Value(s)

Yes

ENGINE DRIVEABILITY AND EMISSIONS

6E–231

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.

Step

Action

Value(s)

Yes

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

—

Go to Step 2

Go to 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 visual/physical check performed?

—

Go to Step 4

Go to Visual /

physical Check.

1. Check for faulty, plugged or incorrectly installed

PCV valve.

2. Verify that the PCV system is not plugged.

Was a problem found?

—

Verify repair

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 IAC position.

Is the IAC position within the specified values?

20-30 Steps

Go to Step 7

Go to Step 6

1. Visually/physically inspect for the following

conditions:

• Restriction of the air intake system. Check for a

restricted air filter element, or foreign objects
blocking the air intake system.

• Check for objects blocking the IAC passage or

throttle bore, 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/brake booster
hose.

Was a problem found?

—

Verify repair

Go to Step 7

6E–232

ENGINE DRIVEABILITY AND EMISSIONS

1. Using a Tech 2, display the engine coolant

temperature and note the value.

2. Check the resistance of the engine coolant

temperature sensor.

Is the actual resistance near the resistance value in
the chart for the temperature that was noted?

—

Go to Step 8

Replace the

ECT sensor.

Verify repair

1. Using a Tech 2, display the MAP sensor value in

comparison with atmosphere temperature.

2. Check for a faulty, plugged, or incorrectly installed

MAP sensor.

Was the problem found?

—

Verify repair

Go to Step 9

Using Tech 2, monitor throttle position with the engine
idling.
Is the throttle position at the specified value and
steady?

Go to Step 10

Refer to

Diagnostic

Trouble Code

P0123 for

further

diagnosis

Check for proper ignition voltage output with the spark
tester.
Was a problem found?

—

Verify repair

Go to Step 11

1. Remove the spark plugs and check for gas or oil

fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.

2. If spark plugs are fouled, the cause of fouling must

be determined before replacing the spark plugs.

Was a problem found?

—

Verify repair

Go to Step 12

Check for a loose ignition control module ground.
Was a problem found?

—

Verify repair

Go to Step 13

Check items that can cause the engine to run rich.
Refer to DTC P1167 “Fuel Supply System Rich During
Deceleration Fuel Cut Off”.
Was a problem found?

—

Verify repair

Go to Step 14

Check items that can cause the engine to run lean.
Refer to DTC P1171 “Fuel Supply System Lean
During Power Enrichment”.
Was a problem found?

—

Verify repair

Go to Step 15

Check the injector connectors, if any of the injectors
are connected any incorrect cylinder, correct as
necessary.
Was a problem found?

—

Verify repair

Go to Step 16

1. Check for faulty engine mounts.

2. If a problem is found, repair as necessary.

Was a problem found?

—

Verify repair

Go to Step 17

Step

Action

Value(s)

Yes

Temperature (°C)

Resistance (

Ω) (Approximately)

-20

32040

9788

3516

1439

656

327

100

175

120

100

Content .. 245 246 247 248 ..