Fuel line ISUZU KB P190 2007 Workshop Repair Manual

ENGINE DRIVEABILITY AND EMISSIONS 6E–109
• The fuel injector(s).
4. Fuel pressure that drops off during acceleration, cruise, or hard cornering may case a lean condition.
A lean condition can cause a loss of power, surging,
or misfire. A lean condition can be diagnosed using a
Tech 2 Scan Tool.
Following are applicable to the vehicle with
closed Loop System:
If an extremely lean condition occurs, the oxygen
sensor(s) will stop toggling. The oxygen sensor
output voltage(s) will drop below 500 mV. Also, the
fuel injector pulse width will increase.
Important: Make sure the fuel system is not
operating in the “Fuel Cut-Off Mode.”
When the engine is at idle, the manifold pressure is
low (high vacuum). This low pressure (high vacuum)
is applied to the fuel pressure regulator diaphragm.
The low pressure (high vacuum) will offset the
pressure being applied to the fuel pressure regulator
diaphragm by the spring inside the fuel pressure
regulator. When this happens, the result is lower fuel
pressure. The fuel pressure at idle will vary slightly
as the barometric pressure changes, but the fuel
pressure at idle should always be less than the fuel
pressure noted in step 2 with the engine OFF.
16.Check the spark plug associated with a particular
fuel injector for fouling or saturation in order to
determine if that particular fuel injector is leaking. If
checking the spark plug associated with a particular
fuel injector for fouling or saturation does not
determine that a particular fuel injector is leaking,
use the following procedure:
• Remove the fuel rail, but leave the fuel lines and injectors connected to the fuel rail. Refer to Fuel
Rail Assembly in On-Vehicle Service .
• Lift the fuel rail just enough to leave the fuel injector nozzles in the fuel injector ports.
Caution: In order to reduce the risk of fire and
personal injury that may result from fuel
spraying on the engine, verify that the fuel rail is
positioned over the fuel injector ports and verify
that the fuel injector retaining clips are intact.
• Pressurize the fuel system by connecting a 20 amp fused jumper between B+ and the fuel
pump relay connector.
• Visually and physically inspect the fuel injector nozzles for leaks.
17.A rich condition may result from the fuel pressure being above 376 kPa (55 psi). A rich condition may
cause a 45 to set. Driveability conditions associated with rich conditions can include hard starting
(followed by black smoke) and a strong sulfur smell
in the exhaust.
20.This test determines if the high fuel pressure is due to a restricted fuel return line or if the high fuel
pressure is due to a faulty fuel pressure regulator.
21.A lean condition may result from fuel pressure below 333 kPa (48 psi). A lean condition may cause a 44 to
set. Driveability conditions associated with lean
conditions can include hard starting (when the
engine is cold), hesitation, poor driveability, lack of
power, surging, and misfiring.
22.Restricting the fuel return line causes the fuel pressure to rise above the regulated fuel pressure.
Command the fuel pump ON with the scan tool. The
fuel pressure should rise above 376 kPa (55 psi) as
the fuel return line becomes partially closed.
NOTE: Do not allow the fuel pressure to exceed 414
kPa (60 psi). Fuel pressure in excess of 414 kPa (60
psi) may damage the fuel pressure regulator. Caution: To reduce the risk of fire and personal
injury:
• It is necessary to relieve fuel system pressure before connecting a fuel pressure gauge.
Refer to Fuel Pressure Relief Procedure,
below.
• A small amount of fuel may be released when disconnecting the fuel lines. Cover fuel line
fittings with a shop towel before
disconnecting, to catch any fuel that may leak
out. Place the towel in an approved container
when the disconnect is completed.
Fuel Pressure Relief Procedure
1. Remove the fuel cap.
2. Located on the intake manifold which is at the top right part of the engine.
3. Start the engine and allow it to stall.
4. Crank the engine for an additional 3 seconds.
Fuel Pressure Gauge Installation
1. Remove the fuel pressure fitting cap.
2. Install fuel pressure gauge 5-8840-0378-0 to the fuel feed line located on the upper right side of the
engine.
3. Reinstall the fuel pump relay.

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ISUZU KB P190 2007

6E–110 ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Diagnosis
StepAction Value(s) Yes No
1 Was the “On-Board Diagnostic (OBD) System Check” performed? — Go to Step 2Go to
OBD
System Check
2 1. Turn the ignition OFF. 2. Turn the air conditioning system OFF.
3. Relieve fuel system pressure and install the fuel pressure gauge.
4. Turn the ignition ON.
NOTE: The fuel pump will run for approximately 2
seconds. Use the Scan Tool to command the fuel
pump ON.
5. Observe the fuel pressure indicated by the fuel pressure gauge with the fuel pump running.
Is the fuel pressure within the specified limits? 283-376 kPa
(41-55 psi) Go to Step 3Go to Step 17
3 Does the fuel pressure indicated by the fuel pressure gauge remain constant?
NOTE: The fuel pressure will drop when the fuel
pump stops running, then it should stabilize and
remain constant. — Go to Step 4Go to Step 12
4 1. When the vehicle is at normal operating temperature, turn the ignition ON to build fuel
pressure and observe the measurement on the
gauge.
2. Start the engine and observe the fuel pressure gauge.
Did the reading drop by the amount specified after the
engine was started? 21-105 kPa
(3-15 psi) Go to Step 5Go to Step 9
5 Is fuel pressure dropping off during acceleration, cruise, or hard cornering? — Go to Step 6Check for
improper fuel
6 Visually and physically inspect the following items for a restriction:
• The in-line fuel filter.
• The fuel feed line.
Was a restriction found? — Verify repair Go to Step 7
7 Remove the fuel tank and visually and physically inspect the following items:
• The fuel pump strainer for a restriction.
• The fuel line for a leak.
• Verify that the correct fuel pump is in the vehicle.
Was a problem found in any of these areas? — Verify repair Go to Step 8
8 Replace the fuel pump. Is the action complete? — Verify repair —
9 1. Disconnect the vacuum hose from the fuel pressure regulator.
2. With the engine idling, apply 12-14 inches of vacuum to the fuel pressure regulator.
Does the fuel pressure indicated by the fuel pressure
gauge drop by the amount specified? 21-105 kPa
(3-15 psi) Go to Step 10Go to Step 11

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ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–111
10 Locate and repair the loss of vacuum to the fuelpressure regulator.
Is the action complete? — Verify repair —
11 Replace the fuel pressure regulator. Is the action complete? — Verify repair —
12 1. Run the fuel pump with the Scan Tool. 2. After pressure has built up, turn off the pump andclamp the supply hose shut with suitable locking
pliers.
Does the fuel pressure indicated by the fuel pressure
gauge remain constant? — Go to Step 13Go to Step 15
13 Visually inspect the fuel supply line and repair any leaks.
Was a problem found? — Verify repair Go to Step 14
14 Remove the fuel tank and inspect for leaky hose or in- tank fuel line.
Was a problem found? — Verify repair Go to Step 8
15 1. If the pliers are still clamped to the fuel supply hose, remove the locking pliers.
2. With suitable locking pliers, clamp the fuel return line to prevent fuel from returning to the fuel tank.
3. Run the fuel pump with the Scan Tool.
4. After pressure has built up, remove power to the pump.
Does the fuel pressure indicated by the fuel pressure
gauge remain constant? — Go to Step 11Go to Step 16
16 Locate and replace any leaking fuel injector(s). Is the action complete? — Verify repair —
17 Is the fuel pressure indicated by the fuel pressure gauge above the specified limit? 376 kPa
(55 psi) Go to Step 18Go to Step 21
18 1. Relieve the fuel pressure. Refer to the Fuel
Pressure Relief .
2. Disconnect the fuel return line from the fuel rail.
3. Attach a length of flexible hose to the fuel rail return outlet passage.
4. Place the open end of the flexible hose into an approved gasoline container.
5. Run the fuel pump with the Scan Tool.
6. Observe the fuel pressure indicated by the fuel pressure gauge with the fuel pump running.
Is the fuel pressure within the specified limits? 290-376 kPa
(42-55 psi) Go to Step 19Go to Step 20
19 Locate and correct the restriction in the fuel return line.
Is the action complete? — Verify repair —
20 Visually and physically inspect the fuel rail outlet passages for a restriction.
Was a restriction found? — Verify repair Go to Step 11
21 Is the fuel pressure indicated by the fuel pressure gauge above the specified value? 0 kPa (0 psi) Go to Step 22Go to Step 23
Step
Action Value(s) Yes No

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ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–11 5
P0122 A Throttle Position Sensor Low Input TPS output voltage is below 0.14V. The ECM uses 0% condition as
substitute. TPS output voltage is more than 0.14V. 1. Sensor power supply circuit open or short
to ground circuit.
2. Sensor signal circuit open or short to ground circuit.
3. Poor connector connection.
4. TPS malfunction.
5. ECM malfunction. J1-7/
J1-15/
P0123 A Throttle Position Sensor High Input TPS output voltage is more than 4.9V. TPS output voltage is below 4.9V.1. Sensor power supply circuit short to
voltage circuit.
2. Sensor signal circuit short to voltage circuit.
3. Sensor ground circuit open or short to voltage circuit.
4. Poor connector connection.
5. TPS malfunction.
6. ECM malfunction. J1-7/
J1-15/ J1-32
P0131 A O
2 Sensor Circuit Low Voltage (Bank 1
Sensor 1) 1. No DTC relating to MAP sensor, TPS,
EVAP purge, ECT sensor, CKP sensor,
VSS, injector control circuit and ignition
control circuit.
2. Engine coolant temperature is more than 60 deg. C.
3. O
2 sensor bank 1 output voltage is below
50mV in “Closed Loop” condition. “Open Loop” fuel control. O
2 sensor bank 1 output voltage is more
than 50mV. 1. Sensor harness short to ground circuit.
2. O
2 sensor malfunction.
3. ECM malfunction. J2-6/
J2-21
P0132 A O
2 Sensor Circuit High Voltage (Bank 1
Sensor 1) 1. No DTC relating to MAP sensor, TPS,
EVAP purge, ECT sensor, CKP sensor,
VSS, injector control circuit and ignition
control circuit.
2. Engine coolant temperature is more than 60 deg. C.
3. O
2 sensor bank 1 output voltage is more
than 952mV in “Closed Loop” condition. O
2 sensor bank 1 output voltage is below
952mV. 1. Sensor harness short to voltage circuit.
2. O
2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Incorrect fuel pressure.
7. Injector malfunction.
8. ECM malfunction. J2-6/
J2-21
P0134 A O
2 Sensor Circuit No Activity Detected
(Bank 1 Sensor 1) 1. No DTC relating to MAP sensor, TPS,
EVAP purge, ECT sensor, CKP sensor,
VSS, injector control circuit and ignition
control circuit.
2. Engine coolant temperature is more than 60 deg. C.
3. Engine run time is longer than 40 seconds.
4. Mass air flow is more than 7g/s.
5. O
2 sensor bank 1 output voltage is
between 300mV and 600mV. O
2 sensor bank 1 output voltage is below
3 0 0 m V c o n s e c u t i v e l y .
O R
O2 sensor bank 1 output voltage is more
than 600mV consecutively. 1. Sensor harness open circuit.
2. O
2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Incorrect fuel pressure.
7. Injector malfunction.
8. ECM malfunction. J2-6/
J2-21
Code Type
DTC Name DTC Setting Condition Fail-Safe (Back Up)Recovery Condition Related Failure PartsRelated
ECM
Pin No.

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6E–118 ENGINE DRIVEABILITY AND EMISSIONSP1167 D Fuel Supply System Rich During
Deceleration Fuel Cutoff 1. No DTC relating to MAP sensor, TPS,
EVAP purge, ECT sensor, CKP sensor,
VSS, injector control circuit and ignition
control circuit.
2. O
2 sensor bank 1 output voltage is more
than 550mV in deceleration fuel cutoff
mode. No fail-safe function.
O
2 sensor output voltage is below 550mV. 1. Sensor harness open or short to ground
circuit.
2. O
2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. EVAP purge solenoid valve malfunction.
9. Ignition system malfunction.
10. Spark plug malfunction. 11. ECM malfunction. J2-6/
J2-21
P1171 D Fuel Supply System Lean During Power Enrichment 1. No DTC relating to MAP sensor, TPS,
EVAP purge, ECT sensor, CKP sensor,
VSS, injector control circuit and ignition
control circuit.
2. Engine coolant temperature is more than 60deg. C.
3. Mass air flow is below 13.5m/s.
4. O
2 sensor bank 1 output voltage is below
350mV in power enrichment mode. No fail-safe function.
O
2 sensor output voltage is more than
350mV. 1. Sensor harness open or short to ground
circuit.
2. O
2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. ECM malfunction. J2-6/
J2-21
P1625 B ECM System Reset ECM reset has occurred other than “On ”. Engine control disabled. Memory are is OK. 1. Electrical interference.
2. Magnetic interference.
3. ECM malfunction. -
P1626 - Immobilizer No Signal No response from immobilizer control unit. 1. Engine does not start.
2. Check engine lamp flash.No recovery.
1. ECM and immobilizer control unit
communication circuit open circuit, short to
ground circuit or short to voltage circuit.
2. ECM malfunction.
3. Immobilizer control unit malfunction.
4. Transponder key malfunction. J2-23/
J2-32
P1631 - Immobilizer Wrong Signal Received response is not correct. 1. ECM malfunction.
2. Immobilizer control unit malfunction.
3. Transponder key malfunction. -
P1648 - Wrong Security Code Entered Received incorrect security code. 1. ECM malfunction.
2. Immobilizer control unit malfunction.
3. Transponder key malfunction. -
P1649 - Immobilizer Function Not Programmed Immobilizer function is not programmed in the ECM. ECM malfunction.
-
P1693 B Tachometer Output Low Voltage Tacho output circuit short to ground circuit. No fail-safe function. Tacho output circuit is correct condition. 1. Tacho output circuit short to ground circuit.
2. Poor connector connection.
3. ECM malfunction. J2-25
Code Type
DTC Name DTC Setting Condition Fail-Safe (Back Up)Recovery Condition Related Failure PartsRelated
ECM
Pin No.

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6E–156 ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Diagnosis.
• Perform “Injector Balance Test” - Refer to Fuel System Diagnosis.
• Check the EVAP canister for fuel saturation - If full of fuel, check canister control and hoses. Refer to
Evaporative (EVAP) Emission Control System.
• Check for a leak in the fuel pressure regulator diaphragm by checking the vacuum line to the
regulator for the presence of fuel. • An intermittent TPS output will cause the system to
go rich due to a false indication of the engine
accelerating.
• Silicon contamination of the HO2S can also cause a high HO2S voltage to be indicated. This condition is
indicated by a powdery white deposit on the portion
of the HO2S exposed to the exhaust stream. If
contamination is noticed, replace the affected HO2S.
Diagnostic Trouble Code (DTC) P0132
O
2 Sensor Circuit High Voltage (Bank 1 Sensor 1)
Step Action Value(S) Yes No
1 Was the “On-Board Diagnostic (OBD) System Check” performed?
—Go to Step 2Go to
On Board
Diagnostic
(OBD) System Check
2 1. Connect the Tech 2. 2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0: Diagnostic Trouble Code”.
Is the DTC P0132 stored as “Present Failure”? — Go to Step 3Refer to
Diagnostic Aids and Go to Step
3
3 1. Using the Tech2, ignition “On” and engine “Off”. 2. Select “Clear DTC Information” with the Tech2 andclear the DTC information.
3. Operate the vehicle and monitor the “F5: Failed This Ignition” in “F2: DTC Information”.
Was the DTC P0132 stored in this ignition cycle? — Go to Step 4Refer to
Diagnostic Aids and Go to Step
4
4 Check for poor/faulty connection at the O
2 sensor or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
— Verify repair Go to Step 5
5 Using the DVM and check the O
2 sensor circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the the O
2 sensor connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
Approximatly 450mV Go to Step 7Go to Step 6
C56(J2) E77
31 216
V
21
E77

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ISUZU KB P190 2007

6E–212 ENGINE DRIVEABILITY AND EMISSIONS
• Perform “Injector Balance Test” - Refer to Fuel
System Diagnosis .
• Check the EVAP canister for fuel saturation - If full of fuel, check canister control and hoses. Refer to
Evaporative (EVAP) Emission Control System .
• Check for a leak in the fuel pressure regulator diaphragm by checking the vacuum line to toe
regulator for the presence of fuel. • An intermittent TP sensor output will cause the
system to go rich due to a false indication of the
engine accelerating.
• Silicon contamination of the HO2S can also cause a high HO2S voltage to be indicated. This condition is
indicated by a powdery white deposit on the portion
of the HO2S exposed to the exhaust stream. If
contamination is noticed, replace the affected HO2S.
Diagnostic Trouble Code (DTC) P1167
Fuel Supply System Rich During Deceleration Fuel Cutoff
Step Action Value(s) Yes No
1 Was the “On-Board Diagnostic (OBD) System Check” performed?
—Go to Step 2Go to
On Board
Diagnostic
(OBD) System Check
2 1. Connect the Tech 2. 2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0: Diagnostic Trouble Code”.
Is the DTC P1167 stored as “Present Failure”? — Go to Step 3Refer to
Diagnostic Aids and Go to Step
3
3 1. Using the Tech2, ignition “On” and engine “Off”. 2. Select “Clear DTC Information” with the Tech2 andclear the DTC information.
3. Operate the vehicle and monitor the “F5: Failed This Ignition” in “F2: DTC Information”.
Was the DTC P1167 stored in this ignition cycle? — Go to Step 4Refer to
Diagnostic Aids and Go to S tep
4
4 1. Using the Tech 2, ignition “On” and engine “Off”. 2. Monitor the “Throttle Position” in the data display.
Does the Tech 2 indicate correct “Throttle Position” in
accordance with accelerator pedal operation? — Go to Step 6Go to Step 5
5 Check for the following conditions. • Objects blocking the throttle valve.
• Incorrectly installed.
If a problem is found, repair as necessary.
Was the problem found? — Verify repair Go to Step 12
6 1. Using the Tech 2, ignition “On” and engine “On”. 2. Monitor the “Manifold Absolute Pressure” in thedata display.
Does the Tech 2 indicate correct “Manifold Absolute
Pressure” in accordance with engine speed or
acceleration? — Go to Step 8Go to Step 7
7 Remove the MAP sensor and check for the following conditions.
• Objects blocking the air cleaner.
• Objects blocking the MAP sensor.
• Objects blocking the throttle valve.
• Vacuum leaking at intake duct.
• Vacuum leaking at throttle body.
If a problem is found, repair as necessary.
Was the problem found? — Verify repair Go to Step 13

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6E–214 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1171 FUEL SUPPLY SYSTEM LEAN DURING POWER ENRICHMENT
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine control module (ECM) internal circuitry can
identify if the vehicle fuel system is capable of supplying
adequate amounts of fuel during heavy acceleration
(power enrichment). The ECM monitors the voltage of
the oxygen sensor during power enrichment. When a
power enrichment mode of operation is requested
during “Closed Loop” operation (by heavy acceleration), the ECM will provide more fuel to the engine. Under
these conditions the ECM should detect a “rich”
condition (high oxygen sensor voltage). If this “rich”
exhaust is not detected at this time, a Diagnostic
Trouble Code P1171 will set. A plugged fuel filter or
restricted fuel line can prevent adequate amounts of fuel
from being supplied during power enrichment mode.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P1171 D Fuel Supply System Lean During Power Enrichment 1. No DTC relating to MAP sensor, TPS,
EVAP purge, ECT sensor, CKP sensor,
VSS, injector control circuit and ignition
control circuit.
2. Engine coolant temperature is more than 60 deg. C.
3. Mass air flow is below 13.5m/s.
4. O
2 sensor bank 1 output voltage is below
350mV in power enrichment mode. No fail-safe function.

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6E–254 ENGINE DRIVEABILITY AND EMISSIONS
DETONATION/SPARK KNOCK SYMPTOM
DEFINITIONS: A mild to severe ping, usually worse under acceleration. The engine makes a sharp metallic knocking
sound that changes with throttle opening. Prolonged detonation may lead to complete engine tailure.
Step Action Value(s) Yes No
1 Was the “ On-Board Diagnostic (OBD) System Check ”
performed? — Go to Step 2Go to
OBD
System Check
2 1. Perform a bulletin search. 2. If a bulletin that addresses the symptom is found,correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom? — Verify repair Go to Step 3
3 Was a visual/physical check performed? —Go to Step 4Go to
Visual /
physical Check .
4 1. If Tech 2 readings are normal (refer to Typical Scan Data Values) and there are no engine
mechanical faults, fill the fuel tank with a known
quality gasoline.
2. Re-evaluate the vehicle performance.
Is detonation present? — Go to Step 5Verify repair
5 1. Check for obvious overheating problems: • Low engine coolant
• Restricted air flow to radiator
• Incorrect coolant solution
2. If a problem is found, repair as necessary.
Was a problem found? — Verify repair Go to Step 6
6 Check the fuel pressure. Refer to 6E-108 page “ Fuel
System Diagnosis” .
Was a problem found? — Verify repair Go to Step 7
7 1. Using a Tech 2, display the MAP sensor value in comparison with atmosphere temperature.
2. Check for a faulty, plugged, or incorrectly installed MAP sensor.
Was the problem found? — Verify repair Go to Step 8
8 1. Using a Tech 2, display the ECT sensor and IAT sensor value and warm up condition compared
with the typical data.
2. Check the specified value or wire.
Was the problem found? — Verify repair Go to Step 9
9 Observe the throttle position display on the Tech 2 while slowly increasing throttle pedal.
Does the throttle position increase steady with
increasing smoothly?
—Go to Step 10Refer to
Diagnostic
Trouble Code P0123 for further
diagnosis
10 Check the knock sensor wire, shield wire, or installation condition.
Was a problem found? — Verify repair Go to Step 11
11 Check items that can cause the engine to run lean. Refer to DTC P1171 “Fuel Supply System Lean
During Power Enrichment”.
Was a problem found? — Verify repair Go to Step 12

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6E–258 ENGINE DRIVEABILITY AND EMISSIONS
EXCESSIVE EXHAUST EMISSIONS OR ODORS SYMPTOM
DEFINITIONS: Vehicle fails an emission test. There is excessive “rotten egg” smell. (Excessive odors do not
necessarily indicate excessive emissions.)
Step Action Value(s) Yes No
1 Was the “ On-Board Diagnostic (OBD) System Check ”
performed? — Go to Step 2Go to
OBD
System Check
2 1. Perform a bulletin search. 2. If a bulletin that addresses the symptom is found,correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom? — Verify repair Go to Step 3
3 Was a visual/physical check performed? —Go to Step 4Go to
Visual /
physical Check .
4 Does the customer continual accelerate On/Off during cold condition? — System OK Go to Step 5
5 Is the customer using the incorrect fuel type? —Replace with
unleaded fuel Go to Step 6
6 Check for vacuum leaks (vacuum lines, intake manifold, throttle body, etc.)
Were any vacuum leaks found? — Go to Step 17Go to Step 7
7 1. Check fuel cap for proper installation. 2. Secure the fuel cap if necessary.
Was a problem found? — Go to Step 17Go to Step 8
8 Check the fuel pressure. Refer to 6E-108 page “Fuel
System Diagnosis” .
Was a problem found? — Go to Step 17Go to Step 9
9 1. Check for faulty, plugged or incorrectly installed PCV valve.
2. Verify that the PCV system is not plugged.
Was a problem found? — Go to Step 17Go to Step 10
10 Check the injector connectors, if any of the injectors are connected to an incorrect cylinder, correct as
necessary.
Was a problem found? — Go to Step 17Go to Step 11
11 Perform the “Injector Coil/Balance Test
” (Refer to 6E-
98 page).
Was a problem found. — Go to Step 17Go to Step 12
12 Check for a problem with the engine cooling system. Was a problem found? — Go to Step 17Go to Step 13
13 Check EVAP canister for fuel loading. Refer to Evaporative Emission Control System.
Was a problem found? — Go to Step 17Go to Step 14
14 Check the EVAP purge solenoid valve operation. Is the valve operated normally? — Go to Step 17Verify repair &
Go to Step 15
15 Check the exhaust system for a possible restriction: • Damaged or collapsed pipes
• Internal catalytic converter failure
Was a problem found? —Verify repair &
Go to Step 16 Go to Step 17

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