Isuzu Trooper (1998-2002 year). Manual - part 477

 

  Index      Isuzu     Isuzu Trooper - service repair manual 1998-2002 year

 

Search            

 

 

 

 

 

 

 

  

 

Content   ..  475  476  477  478   ..

 

 

Isuzu Trooper (1998-2002 year). Manual - part 477

 

 

6E–278

6VE1 3.5 ENGINE DRIVEABILITY AND EMISSIONS

D

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.

Diagnostic Aids

Check for the following conditions:

D

Poor connection or damaged harness – Inspect the
wiring harness for damage.  If the harness appears to
be OK, observe the Actual EGR Position display on the
Tech 2 while moving connectors and wiring harnesses
related to the EGR valve.  A change in the display will
indicate the location of the fault.

D

Ensure EGR valve is correctly mounted.  See
On-Vehicle Service.

Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs.  This
may assist in diagnosing the condition.

NOTE: If the EGR valve shows signs of excessive heat,
check the exhaust system for blockage (possibly a
plugged catalytic converter) using the “Restricted
Exhaust System Check”.

Test Description

Number(s) below refer to the step number(s) on the
Diagnostic Chart
3. A malfunctioning MAP sensor can set an EGR DTC.

The MAP sensor could send a constant signal which
is not low enough to set a low MAP DTC.  The
constant signal from the MAP sensor also may not
be high enough to set a high MAP DTC. This step
verifies that the MAP sensor is responding.

6E–279

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0401 – EGR Flow Insufficient

 

Step

Action

Value(s)

Yes

No

1

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

—

Go to 

Step 2

Go to 

OBD

System

Check

2

Is DTC P1404 also set?

—

Go to 

DTC

1404

Go to 

Step 3

3

1. Start the engine.
2. Monitor the MAP signal with a Tech 2 while idling.
3. While idling, jab the accelerator pedal about halfway

down and immediately let the engine return to idle.

Did the MAP value on the Tech 2 show an immediate
large change?

—

Go to 

Step 5

Go to 

Step 4

4

Replace the MAP sensor.

Is the action complete?

—

Verify repair

—

5

1. Inspect the exhaust system for modification of

original installed parts or leaks.

2. If a problem was found, repair exhaust system as

necessary.

Was a condition present that required repair?

—

Go to 

Step 8

Go to 

Step 6

6

1. Remove the EGR valve.
2. Visually and physically inspect the pintle, valve

passages and the adapter for excessive deposits or
any kind of a restriction.

3. If a problem is found, clean or replace EGR system

components as necessary.

Was a condition present that required repair?

—

Go to 

Step 8

Go to 

Step 7

7

1. Remove the EGR inlet and outlet pipes from the

exhaust manifold and the intake manifold.

2. Inspect the manifold EGR ports and the EGR inlet

and outlet pipes for a blockage caused by excessive
deposits or other damage.

3. If a problem is found, correct the condition as

necessary.

Was a condition present that required repair?

—

Go to 

Step 8

Check the

Procedure

Refer to

Diagnostic

Aids

8

1. Review and record the Tech 2 Failure Records data.
2. Clear DTC and monitor the Tech 2 System Info

Screen while operating the vehicle as specified in
“Diagnostic Aids”.

3. Using a Tech 2, monitor “DTC” info for DTC P0401

until the DTC P0401 test runs.

4. Note the test result.

Does the Tech 2 indicate DTC P0401 failed this
ignition?

—

—

Repair

complete

6E–280

6VE1 3.5 ENGINE DRIVEABILITY AND EMISSIONS

Diagnostic Trouble Code (DTC) P0402 EGR Pintle Crank Error

D06R200075

Circuit Description

The powertrain control module (PCM) monitors the EGR
valve pintle position input to ensure that the valve
responds properly to commands from the PCM, and to
detect a fault if pintle position is stuck open. If the PCM
detects a pintle position signal indicates more than 21.5%
and more than for 625 msec during cranking, the PCM will
set DTC P0402.

Conditions for Setting the DTC

D

Ignition voltage is between 11 and 16 volts.

D

At Engine revolution less than 600 RPM, EGR pintle
position indicates more than 21.0% and more than for
625 msecs.

Action Taken When the DTC Sets

D

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.

D

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in Failure
Records data.

Conditions for Clearing the MIL/DTC

D

The PCM will turn the MIL “OFF” on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

D

A history DTC P0402 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

D

DTC P0402 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the PCM battery
feed.

Diagnostic Aids

Check for the following conditions:

D

Foreign material on EGR valve between pintle and
seat may cause EGR stuck open. Inspect foreign
material in EGR valve.

D

Excessive carbon deposit may cause unsmooth
operation of EGR valve shaft. Inspect for carbon
deposit and clean up inside of carbon deposit.

D

Poor connection or damaged harness–inspect the
wiring harness for damage If the harness appears to be
OK, observe the EGR actual position display on the
Tech 2 while moving connectors and wiring harnesses
related to EGR valve. A change in the display will
indicate the location of the fault.

NOTE: If the EGR valve shows signs of excessive heat,
check the exhaust system for blockage (possibly a
plugged catalytic converter) using the “Restricted
Exhaust System Check”.

6E–281

6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS

DTC P0402 – EGR Pintle Crank Open Error

 

Step

Action

Value(s)

Yes

No

1

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

—

Go to 

Step 2

Go to 

OBD

System

Check

2

1. Ignition “ON”, engine “OFF”, review and record

Tech 2 Failure Records data.

2. Operate the vehicle within Failure Records

conditions as noted.

3. Using a Tech 2, monitor “DTC” info for DTC P0402

until the DTC P0402 test runs. Note the result.

Does the Tech 2 indicates DTC P0402 failed this
ignition?

—

Go to 

Step 3

Check the

Procedure

Refer to

Diagnostic

Aids

3

1. Disconnect the EGR valve harness connector.
2. Inspect the EGR valve and connectors for damaged

pin or terminals.

Were there any damaged pins or terminals?

—

Go to 

Step 4

Go to 

Step 5

4

Repair the damaged pin or terminal.

Is the action complete?

—

Verify repair

—

5

1. Remove EGR valve from Engine.
2. Inspect EGR valve whether there is any foreign

material between seat and pintle.

Was any foreign material in EGR valve?

—

Go to 

Step 6

Go to 

Step 7

6

1. Remove EGR valve foreign material from EGR

valve and clean up inside.

2. Visually inspect for damage of pintle and seat,

which leakage may occur.

Was there any severe damage which affects function?

—

Go to 

Step 7

Verify repair

Go to 

Step 8

7

1. Reconnect.
2. Ignition “OFF”.
3. Install the Tech 2.
4. Run the engine at idle.
5. On Tech-II, select special function for EGR.
6. Use the “UP” arrow to increase the EGR  from 0% to

40%.

Did EGR work properly?

—

—

Go to 

Step 8

8

Replace the EGR valve.

Does DTC P0402 still fail “DTC” test on the Tech 2?

—

Go to 

Step 9

Verify repair

9

Replace the PCM.

Is the action complete?

—

Verify repair

—

 

 

 

 

 

 

 

Content   ..  475  476  477  478   ..