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Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 769

6E–100

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Engine Cranks But Will Not Run

(Cont'd)

Step

Yes

Value(s)

Action

1. Ignition “OFF”, install a fuel pressure gauge at the

test fitting on the fuel supply line in the engine
compartment. (Use a shop cloth to absorb any fuel
leakage while making the connection.)

2. Ignition “ON”, observe the fuel pressure.

Is the fuel pressure within the specified values, and
does it hold steady?

285 - 375 kPa

(43 – 55 psi)

Go to

Step 6

Go to

Step 5

Is any fuel pressure indicated?

—

Go to

Fuel

System

Electrical Test

Go to

Fuel

System

Diagnosis

Install the switch box J 39021–2 at the injector test
connector and activate an injector.

Did the fuel pressure drop when the injector was
activated?

—

Go to

Step 7

Go to

Step 18

Install an injector test light at the #2 cylinder injector
harness connector.

Does the light blink when the engine is cranked?

—

Go to

Step 8

Go to

Step 24

1. Ignition “ OFF”.
2. Disconnect the 11-pin connector at the ION sensing

module.

3. With a test light to B + , probe each of the 6 exposed

ION sensing module pins, one at a time, while the
engine is cranked. (Use the gray narrow Metri - Pak



flexible female connector from the J - 35616 kit to

make the pin accessible.)

Does the light flash at each pin when the engine is
cranked?

—

Go to

Step 12

Go to

Step 9

1. Remove the 4-pin connector at the ION sensing

module.

2. Ignition “ ON”.
3. Use a test light at the harness connector to verify

that the module is being supplied with B + and
ground.

Was a problem found?

—

Go to

Step 10

Go to

Step 11

Repair the open ignition feed circuit or ground circuit to
the ION sensing module.

Is the action complete?

—

Verify repair

—

Repair the ION sensing module.

Is the action complete?

—

Verify repair

—

1. Reconnect the ION sensing module 11-pin

connector.

2. Remove the electrical connector from each coil.
3. With a test light to B+, probe each of the coil

connectors at the wire which runs to the ION
sensing module.

Does the light flash at each coil connector when the
engine is cranked?

—

Go to

Step 14

Go to

Step 13

Check for an open circuit between the coil and ION
sensing module.

Is the action complete?

—

Verify repair

—

6E–101

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Engine Cranks But Will Not Run

(Cont'd)

Step

Yes

Value(s)

Action

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 YEL
tracer).

Did the test light illuminate?

—

Go to

Step 16

Go to

Step 15

Repair the open ignition feed circuit.

Is the action complete?

—

Verify repair

—

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

Repair the open secondary ground circuit.

Is the action complete?

—

Verify repair

—

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

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

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

Is the action complete?

—

Verify repair

—

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

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–102

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Engine Cranks But Will Not Run

(Cont'd)

Step

Yes

Value(s)

Action

Refer to

Engine Mechanical Diagnosis to diagnose the

following conditions:

Faulty or incorrect camshaft drive belts

Leaking or sticky valves or rings

Excessive valve deposits

Weak valve springs

Incorrect valve timing

Leaking head gasket

Is the action complete?

—

Verify repair

Go to

Step 25

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

Is the engine RPM indicated?

—

Go to

Step 25

Go to

Step 34

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 PCM (female) side of the
7-pin connector.

Is the test light “ON”?

—

Go to

Step 26

Go to

Step 32

1. At the PCM (female) side of the connector, 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

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

Is the test light “ON”?

—

Go to

Step 28

Go to

Step 33

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

Is the action complete?

—

Verify repair

—

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

Check for an open injector driver circuit.

Was a problem found?

—

Verify repair

Go to

Step 33

6E–103

TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Engine Cranks But Will Not Run

(Cont'd)

Step

Yes

Value(s)

Action

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

Verify repair

Go to

Step 8

Repair the ignition feed circuit.

Is the action complete?

—

Verify repair

—

Replace the PCM.

IMPORTANT: The replacement PCM must be
programmed.

Refer to

ON-Vehicle Service in Power Control Module

and Sensors for procedures.

And also refer to latest Service Bulletin.

Check to see if the latest software is released or not.

And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.

Is the action complete?

—

Verify repair

—

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

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

Is the action complete?

—

Verify repair

—

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

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

Is the action complete?

—

Verify repair

—

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

Was a problem found?

—

Verify repair

Go to

Step 39

Replace the CKP position sensor.

Is the action complete?

—

Verify repair

Go to

Step 33

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