2007 ISUZU KB P190 sensor

6E-320 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Turbocharger Control System Check
Description
The position of the turbocharger nozzle is controlled by
the ECM. The ECM utilizes a turbocharger nozzle
control solenoid valve and a boost pressure sensor to
control the turbocharger nozzles. When the engine is
not under load, the turbocharger nozzles are in an open
position, or no boost condition. When the engine is
under load, the ECM commands the control solenoid
valve to close the turbocharger nozzles, thus
increasing the boost. The ECM will vary the boost
dependant upon the load requirements of the engine.
The ECM uses a pulse width modulation (PWM) on the
control circuit to open and control the solenoid valve. Notice:
• This Circuit/ System Testing is only applicable to high output engine.
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing Turbocharger Control System Check
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 a 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 a scan tool.
Is DTC P0045, P0107, P0108, P0112, P0113,
P0116, P0117, P0118, P0234, P0299, P0638,
P0698, P0699, P1196, P1197, P1198, P2227,
P2228 or P2229 also set? —
Go to Applicable DTC Go to Step 3

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ISUZU KB P190 2007

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-321
31. Inspect the following conditions:
• Air leakage around the boost pressuresensor objects that block the sensor hole.
• Air leaking around any of the air induction tubing between the turbocharger and
intake manifold. Check for damaged
components and for loose clamps.
• Misrouted, disconnected or kinked turbocharger nozzle control actuator
vacuum hoses. Refer to Vacuum Hose
Routing Diagram in this section for
correct routing.
• Turbine shaft binding causing lower turbocharger spinning speeds. Refer to
the Turbocharger in engine mechanical
section for diagnosis.
• Turbocharger nozzle control actuator for a stuck condition or slow movement.
Refer to Turbocharger in engine
mechanical section for testing.
• Intake throttle valve sticking. Perform the Intake Throttle Solenoid Control with a
scan tool.
• Restricted air cleaner element, restricted or collapsed air tubing between the air
cleaner and the boost pressure sensor.
• Oil in the air induction tubing causing an incorrect boost pressure sensor signal.
When there is adhesion of oil inside of
tubing, intercooler or turbocharger it
needs to be wiped off.
2. Repair the condition as necessary.
Did you find and correct the condition? —
Go to Step 8 Go to Step 4
4 1. Place the transmission in Neutral and set the
parking brake.
2. Accelerate the engine between idle and W.O.T. (accelerator pedal full travel) many
times while observing the Desired Boost
Pressure and Boost Pressure parameter with
a scan tool.
3. Drive the vehicle that the engine speed is more than 2000 RPM and the Calculated
Engine Load parameter reaches at least 50%
for longer than 10 seconds (such as
acceleration on ramp) while comparing the
Boost Pressure to the Desired Boost
Pressure.
Does the Boost Pressure parameter follow within
the specified value? ±
20 kPa ( ±3
psi)
System OK Go to Step 5
Step
Action Value(s)Yes No

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ISUZU KB P190 2007

6E-328 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Hard Start
ChecksAction
Definition:
The engine cranks OK, but does not start for a long time. The engine does eventually run, or may start but immediately dies.
Preliminary Checks • Diagnostic System Check - Engine Controls.
• Ensure the driver is using the correct starting procedure.
• Inspect the ECM grounds for being clean, tight, and in their proper locations.
• Inspect that the harness connectors are correctly connected.
• Inspect the fuel type and quality.
• Inspect the programmed fuel injector ID code for each cylinder.
• Inspect the Scan Tool Data List in this section.
• Inspect the Service Bulletin.
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the Scan Tool
Data List in this section.
• Compare the Coolant Temperature with the Intake Air Temperature (IAT) and Fuel Temperature (FT) parameters 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 in each circuit or for a skewed sensor.
Notice: The mass air flow (MAF) sensor is heated and as a result the IAT may indicate
a higher than normal intake air temperature if the ignition switch is being ON.
• Observe the Fuel Rail Pressure (FRP) Sensor parameter with the engine OFF. The FRP Sensor should read 0.9 to 1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1 minute. If not, check for high
resistance in each circuit or for a skewed sensor.
• Crankshaft position (CKP) sensor is tight and the sensor rotor is not damaged.
• Camshaft position (CMP) sensor is tight and the timing chain sprocket is not damaged.
Fuel System Checks Inspect the fuel system for the following conditions. Refer to Fuel System Check chart
and appropriate procedure in the Fuel System section.
• Air in the fuel system.
• Water contamination in the fuel.
• Fuel waxing or icing.
• Fuel filter indicator lamp is continuously or frequently turned ON with engine run.
• External fuel leaks or high engine oil level.
• In-tank fuel pump operation. Refer to In-tank Fuel Pump System Check in this section.
• Fuel leak off from the fuel pressure limiter valve and fuel injectors.
• Fuel lines between the fuel tank and fuel supply pump for being crushed, kinked, tightness, cracks and plugged.
• A plugged fuel tank vent valve and hose.
• Inside the fuel tank for any foreign material that may be getting drawn into the fuel line pickup causing a blocked condition.
• Fuel supply pump operation.
Notice: The fuel supply pump must be timed to the engine and adjustment value must
be learned to the ECM.
• Perform the Cylinder Balance Test with a scan tool.
• Perform the Injector Force Drive with a scan tool.
• Observe the FRP Regulator Feedback current on the scan tool.

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ISUZU KB P190 2007

6E-330 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Rough, Unstable, or Incorrect Idle and Stalling
ChecksAction
Definition:
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.
Preliminary Checks • Diagnostic System Check - Engine Controls.
• Remove the air cleaner and check for dirt, or for air ducts being plugged or restricted. Replace as necessary.
• Inspect the ECM grounds for being clean, tight, and in their proper locations.
• Inspect that the harness connectors are correctly connected.
• Inspect the fuel type and quality.
• Inspect the programmed fuel injector ID code for each cylinder.
• Inspect the Scan Tool Data List in this section.
• Inspect the Service Bulletin.
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the Scan Tool
Data List in this section.
• Compare the Coolant Temperature with the Intake Air Temperature (IAT) and Fuel Temperature (FT) parameters 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 in each circuit or for a skewed sensor.
Notice: The mass air flow (MAF) sensor is heated and as a result the IAT may indicate
a higher than normal intake air temperature if the ignition switch is being ON.
• Observe the Fuel Rail Pressure (FRP) Sensor parameter with the engine OFF. The FRP Sensor should read 0.9 to 1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1 minute. If not, check for high
resistance in each circuit or for a skewed sensor.
• Observe the Fuel Rail Pressure parameter at idle in Neutral. The Fuel Rail Pressure should always be within 27 to 33 MPa (3,900 to 4,800 psi) after warm up.
• Crankshaft position (CKP) sensor is tight and the sensor rotor is not damaged.
• Camshaft position (CMP) sensor is tight and the timing chain sprocket is not damaged.
Fuel System Checks Inspect the fuel system for the following conditions. Refer to Fuel System Check Chart
and appropriate procedure in the Fuel System section.
• Air in the fuel system.
• Water contamination in the fuel.
• Fuel waxing or icing.
• Fuel filter indicator lamp is continuously or frequently turned ON with engine run.
• External fuel leaks or high engine oil level.
• In-tank fuel pump operation. Refer to In-tank Fuel Pump System Check in this section.
• Fuel leak off from the fuel pressure limiter valve and fuel injectors.
• Fuel lines between the fuel tank and fuel supply pump for being crushed, kinked, tightness, cracks and plugged.
• A plugged fuel tank vent valve and hose.
• Inside the fuel tank for any foreign material that may be getting drawn into the fuel line pickup causing a blocked condition.
• Fuel supply pump operation.
Notice: The fuel supply pump must be timed to the engine and adjustment value must
be learned to the ECM.
• Perform the Cylinder Balance Test with a scan tool.
• Perform the Injector Force Drive with a scan tool.
• Observe the Fuel Compensation for each cylinder at idle on the scan tool.
• Observe the FRP Regulator Feedback current on the scan tool.

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ISUZU KB P190 2007

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-331
Air Intake System ChecksInspect the air intake system for the following conditions.
• Air cleaner, air intake ducts and charge air cooler for a restriction, holes, or leaks.
• A restriction in the turbocharger inlet duct.
• Intake throttle valve for a stuck condition.
• 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.
Engine Mechanical Checks Inspect the engine mechanical for the following conditions. Refer to the Engine
Mechanical section.
• Poor cylinder compression.
• Improper mechanical timing (timing gear and timing chain).
• Improper valve gap.
• Broken or weak valve springs.
• Worn camshaft lobes.
• Incorrect basic engine parts such as camshaft, cylinder head, pistons, etc..
Additional Checks • 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 injector solenoid valve wiring, near the sensor circuits.
• Faulty engine mounts.
• Faulty crank pulley.
• Faulty generator & A/C compressor.
• Generator output voltage.
• EGR system operating correctly. Refer to EGR Control System Check in this section.
• A/C operation.
Checks
Action

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ISUZU KB P190 2007

6E-332 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
High Idle Speed
ChecksAction
Definition:
Engine idle speed is higher than normal in regardless of engine coolant temperature.
Preliminary Checks • Diagnostic System Check - Engine Controls.
• Inspect that the harness connectors are correctly connected.
• Use the scan tool to compare the engine speed and tachometer on the instrument panel (IP) cluster.
• Inspect the battery voltage. If the battery voltage is less than 11 volts, the ECM set the idle speed 50RPM higher than normal.
• Inspect the A/C operation.
• Inspect the fuel type and quality.
• Inspect the engine oil level.
• Inspect the Scan Tool Data List in this section.
• Inspect the Service Bulletin.
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the Scan Tool
Data List in this section.
• Compare the Coolant Temperature with the Intake Air Temperature (IAT) and Fuel Temperature (FT) parameters 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 in each circuit or for a skewed sensor.
Notice: The mass air flow (MAF) sensor is heated and as a result the IAT may indicate
a higher than normal intake air temperature if the ignition switch is being ON.
• Observe the Fuel Rail Pressure (FRP) Sensor parameter with the engine OFF. The FRP Sensor should read 0.9 to 1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1 minute. If not, check for high
resistance in each circuit or for a skewed sensor.
• Observe the Fuel Rail Pressure parameter at idle in Neutral. The Fuel Rail Pressure should always be within 27 to 33 MPa (3,900 to 4,800 psi) after warm up.
• Observe the Accelerator Pedal Position (APP). APP parameter should change linearly from 0 to 100% according to the accelerator pedal operation.
Fuel System Checks Inspect the fuel system for the following conditions. Refer to the Fuel System section.
• Fuel injectors. Remove the injectors and visually inspect. (Injector tip(s) may be damaged)

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ISUZU KB P190 2007

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-333
Cuts Out
ChecksAction
Definition:
A constant jerking that follows the engine speed, usually more pronounced as the engine load increase. The exhaust has a
steady spitting sound at idle, low speed, or hard acceleration for the fuel starvation that can cause the engine to cut-out.
Preliminary Check • Diagnostic System Check - Engine Controls.
• Inspect that the harness connectors are correctly connected.
• Inspect the ECM grounds for being clean, tight, and in their proper locations.
• Inspect the Scan Tool Data List in this section.
• Inspect the Service Bulletin.
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the Scan Tool
Data List in this section.
• Observe the Mass Air Flow (MAF) parameter for a skewed or slow MAF sensor.
• Observe the Fuel Rail Pressure (FRP) Sensor parameter with the engine OFF. The FRP Sensor should read 0.9 to 1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1 minute. If not, check for high
resistance in each circuit or for a skewed sensor.
• Observe the Fuel Rail Pressure and Desired Fuel Rail Pressure parameter between idle and W.O.T. (accelerator pedal full travel) in Neutral. Fuel Rail Pressure
parameter should follow within ± 5 MPa ( ± 725 psi) quick enough.
• Observe the Accelerator Pedal Position (APP). APP parameter should change linearly from 0 to 100% according to the accelerator pedal operation.
• Crankshaft position (CKP) sensor is tight and the sensor rotor is not damaged.
Fuel System Checks Inspect the fuel system for the following conditions. Refer to Fuel System Check Chart
and appropriate procedure in the Fuel System section.
• Air in the fuel system.
• Water contamination in the fuel.
• Fuel waxing or icing.
• Fuel filter indicator lamp is continuously or frequently turned ON with engine run.
• In-tank fuel pump operation. Refer to In-tank Fuel Pump System Check in this section.
• Fuel leak off from the fuel pressure limiter valve and fuel injectors.
• Fuel lines between the fuel tank and fuel supply pump for being crushed, kinked, tightness, cracks and plugged.
• Inside the fuel tank for any foreign material that may be getting drawn into the fuel line pickup causing a blocked condition.
• Perform the Cylinder Balance Test with a scan tool.
• Perform the Injector Force Drive with a scan tool.
• Observe the Fuel Compensation for each cylinder at idle on the scan tool.
Air Intake System Checks Inspect the air intake system for the following conditions.
• Air cleaner, air intake ducts and charge air cooler for a restriction, holes, or leaks.
• A restriction in the turbocharger inlet duct.
• Intake throttle valve for a stuck condition.
• A restriction or leak in the intake manifold.
• A restriction or damaged at MAF sensor.
Exhaust System Checks Inspect the exhaust system for a possible restriction. Refer to the Exhaust System
section.
Additional Checks • 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 injector solenoid valve wiring, near the sensor circuits.

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ISUZU KB P190 2007

6E-334 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Surges
ChecksAction
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.
Preliminary Checks • Diagnostic System Check - Engine Controls.
• Ensure the driver understands the A/C compressor operation.
• Use the scan tool in order to make sure the Vehicle Speed parameter reading matches the vehicle speedometer.
• Inspect the ECM grounds for being clean, tight, and in their proper locations.
• Inspect that the harness connectors are correctly connected.
• Inspect the fuel type and quality.
• Inspect the programmed fuel injector ID code for each cylinder.
• Inspect the Scan Tool Data List in this section.
• Inspect the Service Bulletin.
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the Scan Tool
Data List in this section.
• Observe the Mass Air Flow (MAF) parameter for a skewed or slow MAF sensor.
• Observe the Fuel Rail Pressure (FRP) Sensor parameter with the engine OFF. The FRP Sensor should read 0.9 to 1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1 minute. If not, check for high
resistance in each circuit or for a skewed sensor.
• Observe the Fuel Rail Pressure and Desired Fuel Rail Pressure parameter between idle and W.O.T. (accelerator pedal full travel) in Neutral. Fuel Rail Pressure
parameter should follow within ± 5 MPa ( ± 725 psi) quick enough.
• Observe the Accelerator Pedal Position (APP). APP parameter should change linearly from 0 to 100% according to the accelerator pedal operation.
Fuel System Checks Inspect the fuel system for the following conditions. Refer to Fuel System Check chart
and appropriate procedure in the Fuel System section.
• Air in the fuel system.
• Water contamination in the fuel.
• Fuel waxing or icing.
• Fuel filter indicator lamp is continuously or frequently turned ON with engine run.
• In-tank fuel pump operation. Refer to In-tank Fuel Pump System Check in this section.
• Fuel leak off from the fuel pressure limiter valve and fuel injectors.
• Fuel lines between the fuel tank and fuel supply pump for being crushed, kinked, tightness, cracks and plugged.
• A plugged fuel tank vent valve and hose.
• Inside the fuel tank for any foreign material that may be getting drawn into the fuel line pickup causing a blocked condition.
• Fuel supply pump operation.
Notice: The fuel supply pump must be timed to the engine and adjustment value must
be learned to the ECM.
• Perform the Cylinder Balance Test with a scan tool.
• Perform the Injector Force Drive with a scan tool.

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ISUZU KB P190 2007