ESP ISUZU KB P190 2007 Workshop User Guide

Engine Control System (4JH1) 6E-103
DTC P0216 (Symptom Code A, B) (Flash Code 54)
Description
The engine control module (ECM) calculates the
desired fuel injection quantity and timing using data sent
from various sensors. These desired data are sent to
the fuel injection pump control unit (PCU) via a
controller area network (CAN) communication bus. The
PCU also receives signals from the internal inputs:
pump camshaft position (CMP) sensor that is located
inside the fuel injection pump to determine the cam ring
rotation angle and the fuel injection pump speed. The
fuel temperature (FT) sensor is internal the PCU. These
values are used to compare the desired values sent
from the ECM then PCU determines the injection time
r
piston position and fuel injection quantity, and actuates
timing control valve (TCV) & fuel injection solenoid
valve based on control maps in the PCU.
The timing device changes the optimum injection
timing against various engine conditions. The
pressure of the fuel fed from the feed pump is
adjusted and it acts to the timing plunger by TCV
controlled fuel pressure. (
The TCV is installed to the
fuel injection pump rear side and it is controlled by dut
y
ratio cycle from the PCU.) The timing plunger is
connected to the cam ring by a ball pin. Axial
movement of the timing plunger is transferred to the
cam ring in the form of rotational movement.
Movement to the right of the timing plunge
r
advances injection timing.
If the PCU detects an
excessive difference between actual and desired fuel
injection timing, this DTC will set.
Condition for Running the DTC
Symptom Code A
• The engine speed is higher than 700 RPM.
• The fuel injection quantity is higher than 4 mg/strk.
Symptom Code B
• The engine speed is higher than 2014 RPM.
Condition for Setting the DTC
Symptom Code A
• The PCU monitored actual fuel injection timing is
advanced more than desired by 3°CA for longe
r
than 12 seconds or retarded more than desired by
6°CA for longer than 12 seconds.
Symptom Code B
• The PCU monitored actual fuel injection timing is
oscillated higher than desired by 5.2°CA.
Action Taken When the DTC Sets
• The ECM illuminates the malfunction indicato
r
lamp (MIL) when the diagnostic runs and fails.
• The ECM limits fuel injection quantity.
Condition for Clearing the MIL/DTC
• The ECM turns OFF the MIL when the diagnostic
runs and does not fail.
• A history DTC clears after 40 consecutive driving
cycles without a fault. Or clear with the scan tool.
Diagnostic Aids
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
Notice:
• The fuel injection pump installation with incorrect
mechanical timing may set this DTC.
• This DTC most likely indicate loss fuel pressure by
restricted fuel line. Inspect the fuel line restriction
between the fuel injection pump and fuel tank.
• The fuel system from the fuel tank(s) to the fuel
injection pump is under a slight vacuum with the
engine running. As a result, air can enter the fuel
system if these connections are not tight or if there
is a crack in one of the fuel hoses. Air in the fuel
system will cause fuel injection pump internal
pressure fluctuations especially at high engine
speed and load, which may set this DTC.
• Improper fuel will cause this DTC to set. Inspect
fuel waxing or icing that is caused by an incorrect
fuel type used in winter season or water intrusion
in the fuel system.
• Contaminated fuel will cause this DTC to set.
Inspect the pipe connector fixing bolt (eye bolt) on
the fuel injection pump suction side.
Important:
If the fuel tank is empty or near empty, air might be
allowed to go into the fuel system. W ith air in the fuel
system, smooth flow of fuel into the fuel injection pump
is interrupted and this DTC may set. Perform bleeding
of fuel system after refilling. Refer to air bleeding
procedure in fuel system section.

DTC P0216 (Symptom Code A, B) (Flash Code 54)

Step Action Value(s) Yes No
1 Did you perform the Diagnostic System Check-
Engine Controls? 
Go to Step 2 Go to Diagnostic
System Check-
Engine Controls

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ISUZU KB P190 2007

6E-104 Engine Control System (4JH1)
Step Action Value(s) Yes No
2 1. Install the scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine and let idle for 30 seconds.
4. Monitor the Diagnostic Trouble Code (DTC) Information with the scan tool.
Is DTC P0335 (Symptom Code B or D), P1335
(Symptom Code A) or P1345 (Symptom Code A)
set? 

Go to Applicable DTC Go to Step 3
3 1. Turn OFF the engine. 2. Place the transmission in park or neutral (P or N) and set the park brake.
3. Start the engine and let engine idle for 30 seconds while observing the Actual Injection
Timing parameter with the scan tool.
4. Accelerate the engine and keep the constant engine speed around 2000 RPM while observing
the Actual Injection Timing parameter with the
scan tool.
5. Accelerate the engine and keep the constant engine speed around 3000 RPM while observing
the Actual Injection Timing parameter with the
scan tool.
Does the Actual Injection Timing parameter follow
the Desired Injection Timing within 2°CA on each
engine speed? 

Go to Diagnostic Aids Go to Step 4
4 1. Turn OFF the ignition. 2. Check the fuel system line connections between the fuel tank and the fuel injection pump for
tightness and all fuel hoses for cuts, cracks and
for the use of proper clamps.
Notice: The fuel system from the fuel tank(s) to the
fuel injection pump is under a slight vacuum with the
engine running. As a result, air can enter the fuel
system if these connections are not tight. Air in the
fuel system will cause fuel injection pump internal
pressure fluctuations especially at high engine
speed and load, which may set this DTC.
3. Pump the priming pump on the fuel filter until it becomes firm. If there is a leak on the suction
side of the fuel system between the priming
pump and the fuel injection pump, the priming
pump will not build up sufficient firmness and fuel
leakage may occur.
4. Repair or replace as necessary.
Did you find and correct the condition? 

Go to Step 9 Go to Step 5

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ISUZU KB P190 2007

Engine Control System (4JH1) 6E-219
DTC P1612 (Symptom Code A) (Flash Code 56)
Circuit Description
The engine control module (ECM) communicates with
the immobilizer control unit (ICU) to execute immobilize
r
function. The ECM sends request signal to the ICU. The
ECM receives response signal from the ICU. Both
communication signals are carried out through the
Keyword 2000 serial data link. If the ECM receives
wrong response signal from the ICU, this DTC will set.
Condition for Setting the DTC
• The ECM receives wrong immobilizer response
signal from the ICU.
Action Taken When the DTC Sets • The ECM illuminates the malfunction indicato
r
lamp (MIL) when the diagnostic runs and fails.
• The desired fuel injection quantity is set 0 mg/strk.
Condition for Clearing the MIL/DTC
• The ECM turns OFF the MIL when the diagnostic
runs and does not fail.
• A history DTC clears after 40 consecutive driving
cycles without a fault. Or clear with the scan tool.
Diagnostic Aids • Non programmed ECM may set this DTC.
• Electrical or magnetic interference may affect
intermittent condition.
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
Notice: • Keyword 2000 serial data link circuit problem may
cause this DTC set. The scan tool will not
communicate. Refer to scan tool Does Not
Communicate with Keyword 2000 Device in this
section.
• ECM with wrong specification may set this DTC.

DTC P1612 (Symptom Code A) (Flash Code 56)

Step Action Value(s) Yes No
1 Did you perform the Diagnostic System Check-
Engine Controls? 
Go to Step 2 Go to Diagnostic
System Check-
Engine Controls
2 1. Install the scan tool. 2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Select the “Immobilizer” in the system selection menu.
5. Monitor the Diagnostic Trouble Code (DTC) Info Ordered By Priority with the scan tool.
Does the immobilizer DTCs fail this ignition which
begin with B? 

Go to Applicable
DTC in Immobilizer Section Go to Step 3
3 Monitor the DTC Information with the scan tool. Does the DTC fail this ignition? 

Go to Step 4 Go to Diagnostic
Aids
4 Program or reprogram immobilizer function into the engine control module (ECM). Refer to Programming
Engine Control Module (ECM) in immobilizer section.
Did you find and correct the condition? 

Go to Step 6 Go to Step 5
5 Important: Replacement ECM must be
programmed.
Replace the ECM. Refer to Engine Control Module
(ECM) Replacement in this section.
Did you complete the replacement? 

Go to Step 6 
6 1. Clear the DTCs with the scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Monitor the DTC Information with the scan tool.
Did the DTC fail this ignition? 

Go to Step 2 Go to Step 7
7 Observe the DTC Information with the scan tool. Are there any DTCs that you have not diagnosed?  Go to Diagnostic
Trouble Code (DTC) List System OK

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ISUZU KB P190 2007

6E-220 Engine Control System (4JH1)
DTC P1613 (Symptom Code A) (Flash Code 56)
Circuit Description
The engine control module (ECM) communicates with
the immobilizer control unit (ICU) to execute immobilize
r
function. The ECM sends request signal to the ICU. The
ECM receives response signal from the ICU. Both
communication signals are carried out through the
Keyword 2000 serial data link. If the ECM does not
detect response signal from the ICU, this DTC will set.
Condition for Setting the DTC
• The ECM does not receive the immobilize
r
response signal from the ICU.
Action Taken When the DTC Sets • The ECM illuminates the malfunction indicato
r
lamp (MIL) when the diagnostic runs and fails.
• The desired fuel injection quantity is set 0 mg/strk.
Condition for Clearing the MIL/DTC • The ECM turns OFF the MIL when the diagnostic
runs and does not fail.
• A history DTC clears after 40 consecutive driving
cycles without a fault. Or clear with the scan tool.
Diagnostic Aids
• Non programmed ECM may set this DTC.
• Transponder key problem may set this DTC.
• Antenna coil problem may set this DTC.
• Electrical or magnetic interference may affect
intermittent condition.
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
Notice: • Keyword 2000 serial data link circuit problem ma
y
cause this DTC set. The scan tool will not
communicate. Refer to scan tool Does Not
Communicate with Keyword 2000 Device in this
section.
• ECM with wrong specification may set this DTC.

DTC P1613 (Symptom Code A) (Flash Code 56)


Step Action Value(s) Yes No
1 Did you perform the Diagnostic System Check-
Engine Controls? 
Go to Step 2 Go to Diagnostic
System Check-
Engine Controls
2 1. Install the scan tool. 2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Select the “Immobilizer” in the system selection menu.
5. Monitor the Diagnostic Trouble Code (DTC) Info Ordered By Priority with the scan tool.
Does the immobilizer DTCs fail this ignition which
begin with B? 

Go to Applicable
DTC in Immobilizer Section Go to Step 3
3 Monitor the DTC Information with the scan tool. Does the DTC fail this ignition? 

Go to Step 4 Go to Diagnostic
Aids
4 Program or reprogram immobilizer function into the engine control module (ECM). Refer to Programming
Engine Control Module (ECM) in immobilizer section.
Did you find and correct the condition? 

Go to Step 6 Go to Step 5
5 Important: Replacement ECM must be
programmed.
Replace the ECM. Refer to Engine Control Module
(ECM) Replacement in this section.
Did you complete the replacement? 

Go to Step 6 
6 1. Clear the DTCs with the scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Monitor the DTC Information with the scan tool.
Did the DTC fail this ignition? 

Go to Step 2 Go to Step 7
7 Observe the DTC Information with the scan tool. Are there any DTCs that you have not diagnosed?  Go to Diagnostic
Trouble Code (DTC) List System OK


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ISUZU KB P190 2007

Engine Control System (4JH1) 6E-221
DTC P1614 (Symptom Code A) (Flash Code 56)
Circuit Description
The engine control module (ECM) communicates with
the immobilizer control unit (ICU) to execute immobilize
r
function. The ECM sends request signal to the ICU. The
ECM receives response signal from the ICU. Both
communication signals are carried out through the
Keyword 2000 serial data link. If ICU receives wrong
immobilizer response signal from the transponder key,
this DTC will set.
Condition for Setting the DTC
• The ICU receives wrong immobilizer response
signal from the transponder key.
Action Taken When the DTC Sets
• The ECM illuminates the malfunction indicato
r
lamp (MIL) when the diagnostic runs and fails.
• The desired fuel injection quantity is set 0 mg/strk.
Condition for Clearing the MIL/DTC • The ECM turns OFF the MIL when the diagnostic
runs and does not fail.
• A history DTC clears after 40 consecutive driving
cycles without a fault. Or clear with the scan tool.
Diagnostic Aids • Non programmed ICU may set this DTC.
• Transponder key problem may set this DTC.
• ECM with wrong specification may set this DTC.

DTC P1614 (Symptom Code A) (Flash Code 56)

Step Action Value(s) Yes No
1 Did you perform the Diagnostic System Check-
Engine Controls? 
Go to Step 2 Go to Diagnostic
System Check-
Engine Controls
2 1. Install the scan tool. 2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Select the “Immobilizer” in the system selection menu.
5. Monitor the Diagnostic Trouble Code (DTC) Info Ordered By Priority with the scan tool.
Does the immobilizer DTCs fail this ignition which
begin with B? 

Go to Applicable
DTC in Immobilizer Section Go to Step 3
3 Monitor the DTC Information with the scan tool. Does the DTC fail this ignition? 

Go to Step 4 Go to Diagnostic
Aids
4 Program or reprogram immobilizer function into the immobilizer control unit (ICU). Refer to Programming
Immobilizer Control Unit (ICU) in immobilizer
section.
Did you find and correct the condition? 

Go to Step 6 Go to Step 5
5 Important: Replacement ICU must be programmed.
Replace the ICU. Refer to Immobilizer Control Unit
(ICU) Replacement in the immobilizer section.
Did you complete the replacement? 

Go to Step 6 
6 1. Clear the DTCs with the scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Monitor the DTC Information with the scan tool.
Did the DTC fail this ignition? 

Go to Step 2 Go to Step 7
7 Observe the DTC Information with the scan tool. Are there any DTCs that you have not diagnosed?  Go to Diagnostic
Trouble Code (DTC) List System OK


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Engine Control System (4JH1) 6E-259
Checks Action
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the scan tool
Data List in this section.
• Use the scan tool to compare the Engine Coolant Temperature (ECT) with the Intake
Air Temperature (IAT) and Fuel Temperature (FT) on a cold engine condition. If the
difference among temperature reading is more than 5°C (9°F) on a cold engine,
check for high resistance on the low reference circuit and signal circuit or for a
skewed sensor.
Notice: The mass air flow (MAF) sensor is heated and as a result the IAT sensor may
indicate a higher than normal intake air temperature if the ignition switch is being ON.
FT sensor is internal to the PCU and it is part of the fuel injection pump assembly.
• Inspect the crankshaft position (CKP) sensor is tight and the flywheel circumference
is not damaged.
Fuel System Checks Inspect the fuel system for the following conditions. Refer to the Fuel System section.
• Inspect for water contamination in the fuel.
• Inspect for external fuel leaks or fuel leakage into the engine oil.
• Inspect the fuel lines between the fuel tank and fuel injection pump for tightness and
all fuel hoses for cuts, cracks and for the use of proper clamps.
Notice: The fuel system from the fuel tank(s) to the fuel injection pump is under a
slight vacuum with the engine running. As a result, air can enter the fuel system if
these connections are not tight. Air in the fuel system will cause fuel injection pump
internal pressure fluctuations especially at high engine speed and load.
• Inspect for air in the fuel system.
Notice: If many air bubbles appear in the fuel, check the fuel system line connections
between the fuel tank and the fuel injection pump for tightness and all fuel hoses for
cuts, cracks and for the use of proper clamps.
a. Remove the fuel hose that connects to the fuel injection pump suction side.
b. Substitute a clear hose.
Notice: A hose must be cleaned.
c. Connect the clear hose to the fuel injection pump.
d. Bleed the fuel system.
e. Let the engine run at idle for at least 2 minutes.
f. Accelerator the engine between idle and W .O.T. (accelerator pedal full travel) many times while observing the clear hose.
• Inspect the fuel tank vent hose for a plugged or kinked.
• Inspect inside the fuel tank for any foreign material that may be getting drawn into
the fuel line pickup causing a blocked condition. Draw fuel from the fuel tank at the
fuel line (as close to the fuel tank as possible) going to the fuel pickup tube to verify a
clean stream of fuel comes out (use the hand-held vacuum pump 5-8840-0279-0/J-
23738-A with a clear hose or equivalent). This will ensure the fuel pickup tube is not
cracked drawing air into the fuel line.
• Inspect the fuel injection pump operation.
Notice: The fuel injection pump must be timed to the engine.
• Inspect the eye bolt for any type of restriction or collapsed gauze filter.
Notice: If any type of restriction found, check for a condition that causes contaminated
fuel, such as the customer is using an aftermarket fuel filter or extended maintenance
interval. Also inspect fuel waxing or icing that is caused by an incorrect fuel type used
in winter season or water intrusion in the fuel system.
• Inspect the fuel injection nozzle(s) for proper splay condition or operating pressure.
Notice: Only first stage of operating pressure can be checked.
Air Intake System Checks Inspect the air intake system for the following conditions.
• Inspect the air cleaner and air intake ducts for a restriction, holes, or leaks.
• Inspect for a restriction in the turbocharger inlet duct.
• Inspect for a restriction or deposit in the intake throttle bore.
• Inspect for a restriction or leak in the intake manifold.
Exhaust System Checks Inspect the exhaust system for a possible restriction. Refer to the Exhaust System
section.
• Inspect for a restriction in the catalytic converter or exhaust pipes.

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Engine Control System (4JH1) 6E-261
Checks Action
Fuel System Checks Inspect the fuel system for the following conditions. Refer to the Fuel System section.
• Inspect for water contamination in the fuel.
• Inspect for external fuel leaks or fuel leakage into the engine oil.
• Inspect the fuel lines between the fuel tank and fuel injection pump for tightness and all
fuel hoses for cuts, cracks and for the use of proper clamps.
Notice: The fuel system from the fuel tank(s) to the fuel injection pump is under a slight
vacuum with the engine running. As a result, air can enter the fuel system if these
connections are not tight. Air in the fuel system will cause fuel injection pump internal
pressure fluctuations especially at high engine speed and load.
• Inspect for air in the fuel system.
Notice: If many air bubbles appear in the fuel, check the fuel system line connections
between the fuel tank and the fuel injection pump for tightness and all fuel hoses for cuts,
cracks and for the use of proper clamps.
a. Remove the fuel hose that connects to the fuel injection pump suction side.
b. Substitute a clear hose.
Notice: A hose must be cleaned.
d. Connect the clear hose to the fuel injection pump.
c. Bleed the fuel system.
e. Let the engine run at idle for at least 2 minutes.
f. Accelerator the engine between idle and W .O.T. (accelerator pedal full travel) many times while observing the clear hose.
• Inspect the fuel tank vent hose for a plugged or kinked.
• Inspect inside the fuel tank for any foreign material that may be getting drawn into the
fuel line pickup causing a blocked condition. Draw fuel from the fuel tank at the fuel line
(as close to the fuel tank as possible) going to the fuel pickup tube to verify a clean
stream of fuel comes out (use the hand-held vacuum pump 5-8840-0279-0/J-23738-A
with a clear hose or equivalent). This will ensure the fuel pickup tube is not cracked
drawing air into the fuel line.
• Inspect the fuel injection pump operation.
Notice: The fuel injection pump must be timed to the engine.
• Inspect the eye bolt for any type of restriction or collapsed gauze filter.
Notice: If any type of restriction found, check for a condition that causes contaminated
fuel, such as the customer is using an aftermarket fuel filter or extended maintenance
interval. Also inspect fuel waxing or icing that is caused by an incorrect fuel type used in
winter season or water intrusion in the fuel system.
• Inspect the fuel injection nozzle(s) for proper splay condition or operating pressure.
Notice: Only first stage of operating pressure can be checked.
Air Intake System Checks Inspect the air intake system for the following conditions.
• Inspect the air cleaner and air intake ducts for a restriction, holes, or leaks.
• Inspect for a restriction in the turbocharger inlet duct.
• Inspect for a restriction or deposit in the intake throttle bore.
• Inspect for a restriction or leak in the intake manifold.
• Inspect for a restriction or damage at MAF sensor.
Exhaust System Checks Inspect the exhaust system for a possible restriction. Refer to the Exhaust System section.
• Inspect for a restriction in the catalytic converter or exhaust pipes.
Engine Mechanical Checks Inspect the engine mechanical for the following conditions. Refer to the Engine Mechanical
section.
• Inspect for poor cylinder compression. Proper compression is more than 2100 kPa (309
psi).
• Improper mechanical timing
• Improper valve gap
• Broken or weak valve springs
• W orn camshaft lobes
• Inspect for incorrect basic engine parts.

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Engine Control System (4JH1) 6E-263
Checks Action
Fuel System Checks Inspect the fuel system for the following conditions. Refer to the Fuel System section.
• Inspect for water contamination in the fuel.
• Inspect for external fuel leaks or fuel leakage into the engine oil.
• Inspect the fuel lines between the fuel tank and fuel injection pump for tightness and
all fuel hoses for cuts, cracks and for the use of proper clamps.
Notice: The fuel system from the fuel tank(s) to the fuel injection pump is under a
slight vacuum with the engine running. As a result, air can enter the fuel system if
these connections are not tight. Air in the fuel system will cause fuel injection pump
internal pressure fluctuations especially at high engine speed and load.
• Inspect for air in the fuel system.
Notice: If many air bubbles appear in the fuel, check the fuel system line connections
between the fuel tank and the fuel injection pump for tightness and all fuel hoses for
cuts, cracks and for the use of proper clamps.
a. Remove the fuel hose that connects to the fuel injection pump suction side.
b. Substitute a clear hose.
Notice: A hose must be cleaned.
c. Connect the clear hose to the fuel injection pump.
d. Bleed the fuel system.
e. Let the engine run at idle for at least 2 minutes.
f. Accelerator the engine between idle and W .O.T. (accelerator pedal full travel) many times while observing the clear hose.
• Inspect the fuel tank vent hose for a plugged or kinked.
• Inspect inside the fuel tank for any foreign material that may be getting drawn into
the fuel line pickup causing a blocked condition. Draw fuel from the fuel tank at the
fuel line (as close to the fuel tank as possible) going to the fuel pickup tube to verify a
clean stream of fuel comes out (use the hand-held vacuum pump 5-8840-0279-0/J-
23738-A with a clear hose or equivalent). This will ensure the fuel pickup tube is not
cracked drawing air into the fuel line.
• Inspect the fuel injection pump operation.
Notice: The fuel injection pump must be timed to the engine.
Inspect the eye bolt for any type of restriction or collapsed gauze filter.
Notice: If any type of restriction found, check for a condition that causes contaminated
fuel, such as the customer is using an aftermarket fuel filter or extended maintenance
interval. Also inspect fuel waxing or icing that is caused by an incorrect fuel type used
in winter season or water intrusion in the fuel system.
Air Intake System Checks Inspect the air intake system for the following conditions.
• Inspect the air cleaner and air intake ducts for a restriction, holes, or leaks.
• Inspect for a restriction in the turbocharger inlet duct.
• Inspect for a restriction or deposit in the intake throttle bore.
• Inspect for a restriction or leak in the intake manifold.
• Inspect for a restriction or damage at mass air flow (MAF) sensor.
Additional Checks •
Inspect the generator output voltage. Repair if less than 9 volts or more than 16
volts.
• Electromagnetic interference (EMI) on the reference circuit can cause an engine
miss condition. The scan tool can usually detect EMI by monitoring the engine
speed. A sudden increase in speed with little change in actual engine speed change
indicates that EMI is present. If a problem exists, check routing of high voltage
components, such as fuel injection solenoid wiring, near the sensor circuits.


Surges/Chuggles
Checks Action
DIFINITION:The engine has a power variation under a steady throttle or cruise. The vehicle seems to speed up and slow down
with no change in the accelerator pedal.

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Engine Control System (4JH1) 6E-265
Checks Action
Fuel System Checks Inspect the fuel system for the following conditions. Refer to the Fuel System section.
• Inspect for water contamination in the fuel.
• Inspect for external fuel leaks or fuel leakage into the engine oil.
• Inspect the fuel lines between the fuel tank and fuel injection pump for tightness and
all fuel hoses for cuts, cracks and for the use of proper clamps.
Notice: The fuel system from the fuel tank(s) to the fuel injection pump is under a
slight vacuum with the engine running. As a result, air can enter the fuel system if
these connections are not tight. Air in the fuel system will cause fuel injection pump
internal pressure fluctuations especially at high engine speed and load.
• Inspect for air in the fuel system.
Notice: If many air bubbles appear in the fuel, check the fuel system line connections
between the fuel tank and the fuel injection pump for tightness and all fuel hoses for
cuts, cracks and for the use of proper clamps.
a. Remove the fuel hose that connects to the fuel injection pump suction side.
b. Substitute a clear hose.
Notice: A hose must be cleaned.
c. Connect the clear hose to the fuel injection pump.
d. Bleed the fuel system.
e. Let the engine run at idle for at least 2 minutes.
f. Accelerator the engine between idle and W .O.T. (accelerator pedal full travel) many times while observing the clear hose.
• Inspect the fuel tank vent hose for a plugged or kinked.
• Inspect inside the fuel tank for any foreign material that may be getting drawn into
the fuel line pickup causing a blocked condition. Draw fuel from the fuel tank at the
fuel line (as close to the fuel tank as possible) going to the fuel pickup tube to verify a
clean stream of fuel comes out (use the hand-held vacuum pump 5-8840-0279-0/J-
23738-A with a clear hose or equivalent). This will ensure the fuel pickup tube is not
cracked drawing air into the fuel line.
• Inspect the fuel injection pump operation.
Notice: The fuel injection pump must be timed to the engine.
• Inspect the eye bolt for any type of restriction or collapsed gauze filter.
Notice: If any type of restriction found, check for a condition that causes contaminated
fuel, such as the customer is using an aftermarket fuel filter or extended maintenance
interval. Also inspect fuel waxing or icing that is caused by an incorrect fuel type used
in winter season or water intrusion in the fuel system.
• Inspect the fuel injection nozzle(s) for proper splay condition or operating pressure.
Notice: Only first stage of operating pressure can be checked.
• Inspect the timing device operating correctly. Observe the Actual Injection Timing
parameter with the scan tool while running the engine. The Actual Injection Timing
parameter must follow the Desired Injection Timing within 2°CA on each engine
speed. Engine idle > around 2000 RPM> around 3000 RPM. If not, inspect the fuel
system restriction, air in the fuel or fuel injection pump operation.
Air Intake System Checks Inspect the air intake system for the following conditions.
• Inspect the air cleaner and air intake ducts for a restriction, holes, or leaks.
• Inspect for a restriction in the turbocharger inlet duct.
• Inspect for a restriction or deposit in the intake throttle bore.
• Inspect for a restriction or leak in the intake manifold.
• Inspect for a restriction or damage at MAF sensor.
Additional Checks •
Inspect the generator output voltage. Repair if less than 9 volts or more than 16
volts.
• Inspect the EGR system operating correctly.
• Inspect the A/C operation.
• Inspect the torque converter clutch (TCC) operation. (A/T only)



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Engine Control System (4JH1) 6E-267
Checks Action
Fuel System Checks Inspect the fuel system for the following conditions. Refer to the Fuel System section.
• Inspect for water contamination in the fuel.
• Inspect for external fuel leaks or fuel leakage into the engine oil.
• Inspect the fuel lines between the fuel tank and fuel injection pump for tightness and
all fuel hoses for cuts, cracks and for the use of proper clamps.
Notice: The fuel system from the fuel tank(s) to the fuel injection pump is under a
slight vacuum with the engine running. As a result, air can enter the fuel system if
these connections are not tight. Air in the fuel system will cause fuel injection pump
internal pressure fluctuations especially at high engine speed and load.
• Inspect for air in the fuel system.
Notice: If many air bubbles appear in the fuel, check the fuel system line connections
between the fuel tank and the fuel injection pump for tightness and all fuel hoses for
cuts, cracks and for the use of proper clamps.
a. Remove the fuel hose that connects to the fuel injection pump suction side.
b. Substitute a clear hose.
Notice: A hose must be cleaned.
c. Connect the clear hose to the fuel injection pump.
d. Bleed the fuel system.
e. Let the engine run at idle for at least 2 minutes.
f. Accelerator the engine between idle and W .O.T. (accelerator pedal full travel) many times while observing the clear hose.
• Inspect the fuel tank vent hose for a plugged or kinked.
• Inspect inside the fuel tank for any foreign material that may be getting drawn into
the fuel line pickup causing a blocked condition. Draw fuel from the fuel tank at the
fuel line (as close to the fuel tank as possible) going to the fuel pickup tube to verify a
clean stream of fuel comes out (use the hand-held vacuum pump 5-8840-0279-0/J-
23738-A with a clear hose or equivalent). This will ensure the fuel pickup tube is not
cracked drawing air into the fuel line.
• Inspect the fuel injection pump operation.
Notice: The fuel injection pump must be timed to the engine.
• Inspect the eye bolt for any type of restriction or collapsed gauze filter.
Notice: If any type of restriction found, check for a condition that causes contaminated
fuel, such as the customer is using an aftermarket fuel filter or extended maintenance
interval. Also inspect fuel waxing or icing that is caused by an incorrect fuel type used
in winter season or water intrusion in the fuel system.
Inspect the fuel injection nozzle(s) for proper splay condition or operating pressure.
Notice: Only first stage of operating pressure can be checked.
• Inspect the timing device operating correctly. Observe the Actual Injection Timing
parameter with the scan tool while running the engine. The Actual Injection Timing
parameter must follow the Desired Injection Timing within 2°CA on each engine
speed. Engine idle > around 2000 RPM> around 3000 RPM. If not, inspect the fuel
system restriction, air in the fuel or fuel injection pump operation.
Air Intake System Checks Inspect the air intake system for the following conditions.
• Inspect the air cleaner and air intake ducts for a restriction, holes, or leaks.
• Inspect for a restriction or leak in the intercooler.
• Inspect for a restriction in the turbocharger inlet duct.
• Inspect for a restriction or deposit in the intake throttle bore.
• Inspect for a restriction or leak in the intake manifold.
• Inspect for a restriction or damage at MAF sensor.
• Inspect for a worn or damaged turbocharger turbine wheel, shaft or compressor
wheel. Refer to turbocharger inspection in the Engine Mechanical section.
• Inspect for turbocharger wastegate valve operation. Refer to wastegate valve
inspection in the Engine Mechanical section.
Exhaust System Checks Inspect the exhaust system for a possible restriction. Refer to the Exhaust System
section.
• Inspect for a restriction in the catalytic converter or exhaust pipes.

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ISUZU KB P190 2007