Isuzu D-Max / Isuzu Rodeo (TFR/TFS). Manual - part 833

6E–61

3.2L ENGINE DRIVEABILITY AND EMISSIONS

Engine Cranks But Will Not Run

  (Cont'd)

Step

No

Yes

Value(s)

Action

14

1. Ignition “ON.”
2. While the coil connectors are disconnected, touch

each coil connector’s ignition feed terminal with a
grounded test light (the ignition feed wire is black
with orange tracer).

Did the test light illuminate?

—

Go to 

Step 16

Go to 

Step 15

15

Repair the open ignition feed circuit.

Is the action complete?

—

Verify repair

—

16

While the coil connectors are disconnected, touch
each connector’s secondary ground terminal with a
test light to B+.  (The ground wires are black.)

Did the test light illuminate at each coil connector?

—

Go to 

Step 18

Go to 

Step 17

17

Repair the open secondary ground circuit.

Is the action complete?

—

Verify repair

—

18

1. Test the fuel for contamination.
2. If a problem is found, clean the fuel system and

correct the contaminated fuel condition as
necessary.  Replace the fuel filter and replace any
injectors that are not delivering fuel (see Injector
Balance Test).

Was a problem found?

—

Verify repair

Go to 

Step 19

19

1. Remove any ignition coil and install a spark tester at

the spark plug end of the coil.

2. Observe the tester while the engine is cranking.

Was a crisp, blue spark observed?  Only one or two
sparks followed by no result is considered the same as
“No Spark.”

—

Go to 

Step 21

Go to 

Step 20

20

Replace the ignition coil, and return to Step 19 to test
the remaining coils.

Is the action complete?

—

Verify repair

—

21

Repeat Step 19 for each coil.  Remove only one coil at a
time, and reinstall each coil on its spark plug after
testing, but do not refasten coils with screws at this
time.

After all coils have passed the spark test, does the
engine start?

—

Refasten all

coils with

their screws

Go to 

Step 22

22

1. Remove the spark plugs from all cylinders.
2. Visually inspect the spark plug electrodes.
3. Replace any spark plugs with loose or missing

electrodes or cracked insulators.

Did your inspection reveal any spark plugs exhibiting
excessive fouling?

—

Correct the

fouling

condition

Go to 

Step 23

6E–62

3.2L ENGINE DRIVEABILITY AND EMISSIONS

Engine Cranks But Will Not Run

  (Cont'd)

Step

No

Yes

Value(s)

Action

23

Refer to 

Engine Mechanical Diagnosis to diagnose the

following conditions:

D

Faulty or incorrect camshaft drive belts

D

Leaking or sticky valves or rings

D

Excessive valve deposits

D

Loose or worn rocker arms

D

Weak valve springs

D

Incorrect valve timing

D

Leaking head gasket

Is the action complete?

—

Verify repair

Go to 

Step 25

24

Observe the “Engine Speed” data display on the Tech 2
while cranking the engine.

Is the engine RPM indicated?  (If the Tech 2 is normally
powered from the cigarette lighter socket, and if the
Tech 2 display goes blank while cranking the engine, it
will be necessary to power the Tech 2 directly from the
vehicle battery.)

—

Go to 

Step 25

Go to 

Step 34

25

1. Disconnect the 7-pin gray connector at the rear of

the air filter beneath the point where the air duct
attaches to the MAF sensor.

2. Ignition “ON.”
3. Using a test light connected to ground, probe the

ignition terminal at the ECM (female) side of the
7-pin connector.

Is the test light “ON?”

—

Go to 

Step 26

Go to 

Step 32

26

1. At the ECM (female) side of the connector

mentioned in step 25, connect a test light between
the ignition + terminal and one of the injector driver
circuits at the same connector.

2. Ignition “ON.”
3. Observe the test light, and repeat the test for each

injector driver circuit.

Did the test light stay on when checking any of the 6
injector driver circuits?

—

Go to 

Step 27

Go to 

Step 29

27

1. Ignition “OFF,” disconnect the ECM.
2. Ignition “ON,” observe the test light.

Is the test light “ON?”

—

Go to 

Step 28

Go to 

Step 33

28

Locate and repair the short to ground in the injector
driver circuit.

Is the action complete?

—

Verify repair

—

29

1. Using the same test location as in step 26, connect

a test light between the ignition terminal and one of
the driver circuits.

2. Crank the engine and observe the test light.
3. Repeat for each injector driver circuit.

Did the light blink during the test for each circuit?

—

Go to 

Step 31

Go to 

Step 30

30

Check for an open injector driver circuit.

Was a problem found?

—

Verify repair

Go to 

Step 33

6E–63

3.2L ENGINE DRIVEABILITY AND EMISSIONS

Engine Cranks But Will Not Run

  (Cont'd)

Step

No

Yes

Value(s)

Action

31

1. At the injector (male) side of the gray connector

mentioned in step 25, connect an ohmmeter
between the ignition pin and one of the driver circuit
pins.

2. Check for continuity in the circuit.
3. Repeat for each injector circuit.  The readings

should be approximately equal to the  specified
value for injector resistance.

Was a problem found?

12.5 ohms

Verify repair

Go to 

Step 8

32

Repair the ignition feed circuit.

Is the action complete?

—

Verify repair

—

33

Replace the ECM.

Is the action complete?

—

Verify repair

—

34

1. Raise the vehicle and disconnect the CKP sensor

harness.

2. Ignition “ON.”
3. With a test light to ground, probe the harness

ignition feed terminal.

Did the light illuminate?

—

Go to 

Step 36

Go to 

Step 35

35

Check the ignition feed wire between the sensor and
the ECM for a short to ground or open circuit.

Is the action complete?

—

Verify repair

—

36

1. Ignition “ON.”
2. At the CKP harness connector, connect a test light

between the ignition and ground terminals.

Did the light illuminate?

—

Go to 

Step 38

Go to 

Step 37

37

Check the sensor ground circuit for an open or short to
voltage.

Is the action complete?

—

Verify repair

—

38

Check the signal circuit between the sensor and the
ECM for a short to ground, short to voltage, or an open.

Was a problem found?

—

Verify repair

Go to 

Step 39

39

Replace the CKP position sensor.

Is the action complete?

—

Verify repair

Go to 

Step 33

6E–64

3.2L ENGINE DRIVEABILITY AND EMISSIONS

Fuel System Electrical Test

060RW058

Circuit Description

When the ignition switch is first turned “ON,” the Engine
Control Module ECM energizes the fuel pump relay which
applies power to the in-tank fuel pump.  The fuel pump
relay will remain “ON” as long as the engine is running or
cranking and the ECM is receiving 58X crankshaft
position pulses.  If no 58X crankshaft position pulses are
present, the ECM de-energizes the fuel pump relay within
2 seconds after the ignition is turned “ON” or the engine is
stopped.
The fuel pump delivers fuel to the fuel rail and injectors,
then to the fuel pressure regulator.  The fuel pressure
regulator controls fuel pressure by allowing excess fuel to
be returned to the fuel tank.  With the engine stopped and
ignition “ON,” the fuel pump can be turned “ON” by using a
command by the Tech 2.

Diagnostic Aids

An intermittent may be caused by a poor connection,
rubbed-through wire insulation, or a wire broken inside
the insulation.  Check for the following items:

D

Poor connection or damaged harness – Inspect the
ECM harness and connectors for improper mating,
broken locks, improperly formed or damaged
terminals, poor terminal-to-wire connection, and
damaged harness.

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. If the fuel pump is operating but incorrect pressure is

noted, the fuel pump wiring is OK and the “Fuel
System Pressure Test” chart should be used for
diagnosis.