fuel pump ISUZU TROOPER 1995 Owner's Manual

E) REMOVAL
Preparation: Battery ground cable
1. Air cleaner assembly
2. Radiator upper fan shroud
• Remove from radiator.
3. Cooling fan assembly
• Remove four nuts, then the cooling fan
assembly.
4. Accelerator Padal cable
• Disconnect from throttle body and cable
bracket.
5. Canister vacuum hose
• Disconnect from vacuum pipe.
6. Vacuum booster hose
• Disconnect from common chamber.
7. Connectors
• Disconnect from Manifold Absolute Pressure,
canister Vacuum
Switching Valve (VSV),
Exhaust Gas Recirculation VSV, Intake Air
Temperature and ground cable.
8. High tension cables
• Disconnect from cylinder head cover.
9.
Ignition Control Module assembly
• Disconnect three Electronic Ignition con­
nectors.
• Remove three Electronic Ignition bracket fixing
bolts, and remove Electronic Ignition assembly
with high tension cables.
10.
Throttle body
• Remove four fixing bolts.
11. Vacuum hoses
• Disconnect vacuum hoses on canister VSV and
Exhaust Gas Recirculation
VSV from the
throttle body.
12.
Positive Crankcase Ventilation hose
• Disconnect from common chamber.
13.
Fuel Pressure Control Valve vacuum hose
• Disconnect from common chamber.
14.
Evaporative Emission Canister Purge hose
• Disconnect from common chamber.
15.
Exhaust Gas Recirculation Valve assembly
• Remove five bolts from common chamber,
exhaust
manifold and cylinder head cover.
16.
Common chamber duct (DOHC)
• Remove four bolts, four nuts and three bracket
fixing
bolts, then remove the common
chamber duct.
• Disconnect ground cable from rear side of
common chamber.
ENGINE (V6 3.2L DOHC AND SOHC) 6A1-39
17. Common chamber
• Remove six bolts, two nuts and three bracket
fixing
bolts, then remove the common
chamber.
18.
Fuelhoses
• Disconnect feed and return fuel hoses from fuel
pipes, and remove two bracket fixing bolts on
the
cylinder head cover.
19.
Power steering pump drive belt
20. Air Conditioning compressor drive belt
21. Generator drive belt
22. Power steering pump
23. Fan pulley assembly
24. Crankshaft pulley assembly
~ • Using special tool J-8614-01, hold crankshaft
~ pulley.
•
Remove center bolt, then the pulley.
25. Oil cooler hose
• Remove two cooler hose bracket fixing bolts on
the timing
belt cover.
26.
Timing belt cover
27. Pusher
\fl CAUTION:
'if The pusher prevents air from entering the oil
chamber. Its rod must always be facing upward.
28.
Timing belt
CAUTIONS:
1) Do not bend or twist the belt, otherwise its
core
could be damaged. The belt should not
be bent at a radius less than 30mm.
2) Do not allow oil or other chemical substances
to come in contact
with the belt. They will
shorten the belt life.
3) Do not attempt to pry or stretch the belt with a
screwdriver
or any other tool during
installation.
4) Store timing belt in a cool and dark place.
Never expose the belt to direct sunlight or
heat.
29.
Cylinder head cover
30. Camshaft
• Camshaft pulley fixing bolt and camshaft pulley
•
Front plate fixing bolts and front plate
• Chain
tensioner fixing bolts (DOHC) and
camshaft bracket fixing
bolts
•
Camshaft, oil seal and camshaft end plug
31. Swing arm (DOHC)
32. Rocker
arm (SOHC)
•
Fixing bolt and rocker arm
33.
Spark plugs
• Keep valve in home position by feeding the
compressed air to the
cylinder from spark plug
hole.

6A 1-40 ENGINE (V6 3.2L DOHC AND SOHC)
34. Valve springs
35.
• Refer to section 6A "Valve springs oil
controller, valve, valve guide (and HLA for
DOHC)" removal.
Valve stem oil controllers
~·
Using special tool, remove each valve stem oil
controller.
Remover: J-37281
1••1 INSTALLATION
35. Valve stem oil controllers
• Refer to Section 6A "Valve springs, oil
controller, valve, valve guide (and HLA for
DOHC)" installation.
34. Valve springs
li5\l • Using special tool, install each valve spring.
~ Spring compressor: J-39251
33. Spark plugs
~~~· Tighten each spark plug to the specified torque.
Torque
N·m (lb·ft) I 18 (13)
32. Rocker arm (SOHC)
~~~ • Tighten bolt to the specified torque.
Torque
N·m (lb·ft) I 18 (13)
31. Swing arm (DOHC)
30. Camshaft
• Refer to Section 6A "Camshaft installation".
29. Cylinder head cover
~~~ • Tighten bolts to the specified torque.
Torque
N-m (lb·in) I 8 (69)
28. Timing belt
• Refer to "Timing belt removal and installation"
in this section.
27. Pusher
• Tighten bolt to the specified torque.
~~~ Torque N·m (lb·ft) 19 (14)
26. Timing belt cover
• Remove crankshaft pulley that was installed in
step
30.
~~~· Tighten bolts to the specified torque.
Torque
N·m (lb-ft) I 18 (13)
25. Oil cooler hose
~ • Tighten oil cooler hose bracket bolts to the
~ specified torque.
Torque
N-m (lb·ft) I 18 (13)
24. Crankshaft pulley assembly
f'Qil • Using special tool J-8614-01, hold the
~ crankshaft pulley.
~~~· Tighten center bolt to the specified torque.
Torque
N·m (lb·ft) I 167 (123)
23. Fan pulley assembly
~~~ • Tighten fixing bolt to the specified torque.
Torque
N·m (lb·ft) I 22 (16)
22. Power steering pump
~ • Tighten pump fixing bolts to the specified
~ torque.
Torque
N·m (lb·ft) 56 (41)
21. Generator drive belt
• Engage and adjust.
• Refer to Section 6B "Drive belt adjustment".
20. Air Conditioning compressor drive belt
• Engage and adjust.
• Refer to Section 6B "Drive belt adjustment".
19. Power steering pump drive belt
• Engage and adjust.
• Refer to Section 6B "Drive belt adjustment".
18. Fuel hoses
• Connect surely the hoses and install the bolts
on the head cover.
17. Common chamber
~~~· Tighten bolts and nuts to the specified torque.
Bolts
Torque
N-m (lb·ft) 24 (17)
Nuts
Torque
N·m (lb·ft) 24 (17)
16. Common chamber duct (DOHC)
~~~ • Tighten bolts and nuts to the specified torque.
Bolts
Torque
N·m (lb·ft) 24 (17)
Nuts
Torque
N·m (lb·ft) 24 (17)
15. Exhaust Gas Recirculation Valve assembly
~~~· Tighten bolts to the specified torque.
Exhaust gas recirculation valve side
Torque
N·m (lb-in) 8 (69)
Exhaust manifold side
Torque
N-m (lb·ft) 28 (21)
14. Evaporative Emission Canister Purge hose
13. Fuel Pressure Control Valve vacuum hose
12. Positive Crankcase Ventilation hose
10. Throttle body
~~~ • Tighten bolts to the specified torque.
Torque
N-m (lb·ft) I 19 (14)
..

EJ REMOVAL
Preparation: • Remove engine hood.
• Drain radiator Engine Coolant.
• Disconnect battery ground cable.
1. Air cleaner assembly
2. Radiator upper fan shroud
• Remove from radiator.
3. Radiator fan assembly
• Remove four nuts, then the radiator fan
assembly.
4. Accelerator Pedal cable
• Disconnect from throttle body and cable
bracket.
5. Canister vacuum hose
6. Vacuum booster hose
• Disconnect from common chamber.
7. Connectors
• Disconnect from Manifold Absolute Pressure,
canister Vacuum Switching
Valve (VSV),
Exhaust Gas Recirculation VSV,
Intake Air
Temperature and ground cable.
8. High tension cables
• Disconnect from cylinder head cover.
9. Ignition Control Module assembly
• Disconnect three Electronic Ignition con­
nectors.
• Remove three Electronic Ignition bracket fixing
bolts, and remove Electronic Ignition assembly
with high tension cables.
10. Throttle body
• Remove four fixing bolts.
11. Vacuum hoses
• Disconnect vacuum hoses on canister VSV and
Exhaust Gas Recirculation VSV
from the
throttle body.
12. Positive Crankcase Ventilation hose
• Disconnect from common chamber.
13. Fuel Pressure Control Valve vacuum hose
• Disconnect from common chamber.
14. Evaporative Emission Canister Purge hose
• Disconnect from common chamber.
15. Exhaust Gas Recirculation assembly
16. Common chamber
• Remove six bolts, two nuts and four bracket
fixing bolts, then remove the
common
chamber.
17. Throttle body
• Disconnect Engine Coolant hose from throttle
body.
• Disconnect Idler Air Control Valve and Throttle
Position Sensor connectors.
ENGINE (V6 3.2L DOHC AND SOHC) 6A1-43
18. Fuelhoses
• Disconnect feed and return fuel hoses from fuel
pipes, and remove two bracket fixing bolts on
the cylinder head cover.
19. Fuel injector connectors
• Disconnect connectors from injectors.
• Disconnect thermo sensor connector.
20. Intake manifold
• Remove two fixing bolts and four nuts.
21. Engine Coolant manifold
• Disconnect heater hose.
• Remove four fixing bolts.
22. Power steering pump drive belt
23. Air Conditioning compressor drive belt
24. Generator drive belt
25. Power steering pump
26.
Fan pulley assembly
27. Crankshaft pulley assembly
~ • Using special tool J-8614-01, hold crankshaft
~ pulley.
•
Remove center bolt, then the pulley.
28. Oil cooler hose
• Remove two cooler hose bracket fixing bolts on
the timing
belt cover.
29. Timing belt cover
30. Pusher
\fl CAUTION:
VI The pusher prevents air from entering the oil
chamber. Its rod must always be facing upward.
31. Timing belt
\fl CAUTIONS:
VI 1) Do not bend or twist the belt, otherwise its
core
could be damaged. The belt should not
be bent at a radius less than 30mm.
2) Do not allow oil or other chemical substances
to come in contact with the belt. They will
shorten the belt life.
3) Do not attempt to pry or stretch the belt with a
screwdriver
or any other tool during
installation.
4) Store timing belt in a cool and dark place.
Never expose the
belt to direct sunlight or
heat.
32. Cylinder head cover
• Remove 11 fixing bolts, then the cylinder head
cover.
33. Power steering pump bracket
• Disconnect ground cable from bracket.
• Remove five fixing bolts, then the bracket.
34. Exhaust front pipe
35.
Level gage guide tube fixing bolt
• Remove from cylinder head.
36. Cylinder head

'.:.:.
6A1-44 ENGINE (V6 3.2L DOHC AND SOHC)
1••1 INSTALLATION
36. Cylinder head
l"i:a\1 • Using special tools, tighten fixing bolts to the
~ specified torque, in sequence shown in
Fig.
6A 1-53.
Extension wrench: J-39252
Extension wrench: J-24239-01
NOTE:
• Do not reuse cylinder head gasket and M11
fixing bolts.
• Do not apply the oil to the bolt.
M8x1.25
1~1 Torque N·m (lb·ft)
M11x1.5
21 (15)
~~~ Torque N·m (lb·ft) 64 (47)
[ill ® ® @ , , , I I I
~
I
I I
I I
I I I
I I
I I I
I I
I

0
' , , ' ' , ' , ' ® '-~ CD @
M8 Bolt QM11Bolt
Fig. 6A1-53
35. Level gage guide tube fixing bolt
34. Exhaust front pipe
' '
, ,
(j)
I
I
I
@
~~~ • Tighten fixing bolt to the specified torque.
Torque
N·m (lb·ft) I 67 (48)
33. Power steering pump bracket
~~~· Tighten fixing bolts to the specified torque.
Torque
N·m (lb·ft) I 46 (34)
32. Cylinder head cover
• Refer to "Cylinder head cover removal and
installation" in this section.
31. Timing belt
• Refer to "Timing belt removal and installation"
in this section.
30. Pusher
• Tighten bolt to the specified torque.
1~1 Torque N·m (lb·ft) I 19 (14)
29. Timing belt cover
• Remove crankshaft pulley that was installed in
step
33.
~~~· Tighten bolts to the specified torque.
Torque
N·m (lb·ft) I 18 (13)
28. Oil cooler hose
~ • Tighten oil cooler hose bracket bolts to the
~ specified torque.
Torque
N·m(lb·ft) I 18(13)
27. Crankshaft pulley assembly
l"i:a\1 • Using special tool J-8614-01, hold the
~ crankshaft pulley.
~~~· Tighten center bolt to the specified torque.
Torque
N·m (lb·ft) I 167 (123)
26. Fan pulley assembly
~~~ • Tighten fixing bolt to the specified torque.
Torque
N·m (lb·ft) I 22 (16)
25. Power steering pump
~ • Tighten pump fixing bolts to the specified
~ torque.
Torque
N-m (lb·ft) 46 (34)
24. Generator drive belt
• Engage and adjust.
• Refer to Section 68 "Drive belt adjustment".
23. Air Conditioning compressor drive belt
• Engage and adjust.
• Refer to Section 68 "Drive belt adjustment".
22. Power steering pump drive belt
• Engage and adjust.
• Refer to Section 68 "Drive belt adjustment".
21. Engine Coolant manifold
~~~· Tighten fixing bolts to the specified torque.
Torque
N·m (lb·ft) J 22 (16)
• Connect heater hose.
20. Intake manifold
~ • Tighten fixing bolts and nuts to the specified
~ torque.
Bolts
Torque N-m (lb·ft) 24 (17)
Nuts
Torque
N-m (lb·ft) 24 (17)
19. Fuel injector connectors
• Connect to each injector.
18. Fuelhoses
• Connect the hoses securely and install the bolts
on the head cover.
17. Throttle body
..

1••1 REMOVAL
Preparation: • Remove engine hood.
• Drain radiator Engine Coolant.
•
Disconnect battery ground cable.
1.
Air cleaner assembly
2. Radiator upper fan shroud
• Remove from radiator.
3. Radiator fan assembly
• Remove four nuts, then the radiator fan
assembly.
4. Accelerator Pedal cable
• Disconnect from throttle body and cable
bracket.
5. Canister vacuum hose
• Disconnect from vacuum pipe.
6.
Vacuum booster hose
• Disconnect from common chamber.
7. Connectors
• Disconnect from Manifold Absolute Pressure,
canister Vacuum Switching Valve (VSV),
Exhaust
Gas Recirculation VSV, Intake Air
Temperature and ground cable.
8. High tension cables
• Disconnect from cylinder head cover.
9. Ignition Control Module assembly
• Disconnect three Electronic Ignition con­
nectors.
• Remove three Electronic Ignition bracket fixing
bolts, and remove Electronic
Ignition assembly
with high tension cables.
10. Throttle body
• Remove four fixing bolts.
11.
Vacuum hoses
• Disconnect vacuum hoses on canister VSV and
Exhaust
Gas Recirculation VSV from the
throttle body.
12.
Positive Crankcase Ventilation hose
• Disconnect from common chamber.
13. Fuel Pressure
Control Valve vacuum hose
• Disconnect from common chamber.
14.
Canister vacuum hose
• Disconnect from common chamber.
15.
Exhaust Gas Recirculation Valve assembly
• Remove five bolts from common chamber,
exhaust manifold and cylinder head cover.
16.
Common chamber duct
• Remove four bolts, four nuts and three bracket
fixing bolts, then remove the
common
chamber.
• Disconnect ground cable from rear side of
common chamber.
ENGINE (V6 3.2L DOHC AND SOHC) 6A1 47
17. Throttle body
• Disconnect Engine Coolant hose from throttle
body.
• Disconnect Idle Air Control Valve and Throttle
Position Sensor connectors.
18.
Common chamber
• Remove six bolts and two nuts.
• Remove fixing bolts on common chamber
bracket, then the
common chamber.
19.
Fuelhoses
• Disconnect feed and return fuel hoses from fuel
pipes, and remove
two bracket fixing bolts on
the cylinder head cover.
20. Fuel injector connectors
• Disconnect connectors from injectors.
• Disconnect thermo sensor connector.
21.
Intake manifold
• Remove two fixing bolts and four nuts.
22. Engine
Coolant manifold
• Disconnect heater hose.
• Remove four fixing bolts.
23.
Power steering pump drive belt
24. Air Conditioning compressor drive belt
25. Generator drive belt
26. Power steering pump
27. Fan pulley assembly
28. Crankshaft pulley assembly
I®J • Using special tool J-8614-01, hold crankshaft
pulley.
•
Remove center bolt, then the pulley.
29. Oil cooler hose
• Remove two cooler hose bracket fixing bolts on
the timing belt cover.
30. Timing belt cover
31. Pusher
CAUTION:
The pusher prevents air from entering the oil
chamber. Its rod must always be facing upward.
32.
Timing belt
w CAUTIONS:
' 1) Do not bend or twist the belt, otherwise its
core could
be damaged. The belt should not
be bent at a radius less than 30mm.
2) Do not allow oil or other chemical substances
to come in contact
with the belt. They will
shorten the belt life.
3) Do not attempt to pry or stretch the belt with a
screwdriver
or any other tool during
installation.
4) Store timing belt in a cool and dark place.
Never expose the belt to direct sunlight
or
heat.

ENGINE FUEL 6C-1
SECTION 6C
ENGINE FUEL
CONTENTS
General Description ....................... .
Fuel Metering ............................ .
On-Vehicle Service ........................ .
Fuel Filter ................................. .
In Tank Fuel Filter ............................. .
Fuel Pump Flow Test ........................ .
Fuel Pump Assembly ........................ .
Fuel Pump Relay .............................. ..
6C-1
6C-2
6C-3
6C-3
6C-4
6C-4
6C-5
6C-5
Fuel Tank .......................................... ..
Fuel Gage Unit ................................. ..
Fuel Filler Cap .................................... .
Accelerator Pedal Control ............... ..
Accelerator Pedal Control Cable ..
Accelerator Pedal ......................... .
Air
Cleaner Filter ........................... .
Main Data and Specifications ............... .
Torque Specifications ......................
..
6C-6
6C-7
6C-7
6C-8
6C-8
6C-9
6C-10
6C-11
6C-11
GENERAL DESCRIPTION
When working on the fuel system, there are several
things to keep in mind:
• Any time the fuel system is being worked on,
disconnect the negative battery
cable except for
those tests where battery voltage is required.
• Always keep a dry chemical (Class 8) fire extin­
guisher near the work area.
• Replace all pipes with the same pipe and fittings
that were removed.
• Clean and inspect "0" rings. Replace if required.
• Always relieve the line pressure before servicing
any fuel system components.
• Do not attempt repairs on the fuel system until you
have read the instructions and checked the pic­
tures
relating to that repair.
• Adhere to all Notices and Cautions.
All gasoline engines are designed to use only unleaded
gasoline. Unleaded gasoline
must be used for proper
emission control system operation. Its use will also
minimize spark plug fouling and extend engine oil life.
Using leaded gasoline can damage the emission
control system and could result in loss of emission
warranty coverage.
All cars are equipped with an Evaporative Emission
Control System. The purpose of the system is to
minimize the escape offuel vapors to the atmosphere.
Information on this system will be found in Section
6E2.

6C - 4 ENGINE FUEL
I1!]1NSPECTION
After installation, start engine and check for fuel leak­
age.
IN-TANK FUEL FILTER
The filter is located on the lower end of fuel pickup
tube in the fuel tank. It prevents dirt from entering the
fuel pipe and also stops water unless the filter is
completely submerged in the water. It is a self-cleaning
type, not requiring scheduled maintenance. Excess
water and sediment in the tank restricts fuel supply to
the engine, resulting in engine stop. In such a case, the
tank
must be cleaned throughly.
FUEL PUMP FLOW TEST
If reduction of fuel supply is suspected, perform
checking as follows.
Preparation:
• Make sure that there is fuel in the tank.
• With the engine running, check the fuel feed
pipe and hose
from fuel tank to injector for
evidence of leakage.
Retighten, if pipe or hose connection is loose.
Also,
check pipes and hoses for squashing or
clogging.
1. Receive the hose from fuel feed pipe with a clean
container, and check for fuel pump flow rate.
2. Connect the pump relay terminals with a jumper
wire as shown and start the fuel pump to measure
delivery. (Fig. 6C-4)
W CAUTION:
Never generate sparks when connecting a jumper
wire.
Fig. 6C-4
Delivery Delivery
15 seconds 0.38
liters minimum
If the measure value is out of standard, conduct the
pressure test.
Pressure test
For the pressure test to the fuel system, see Section 6E
"Fuel Control System".
II

FUEL PUMP ASSEMBLY
1
ENGINE FUEL 6C-5
Removal steps
1. Fuel tank assembly 2. Fuel pump assembly
Installation
steps
To install, follow the removal steps in the reverse order.
Fig. 6C-5
B REMOVAL
Preparation:
• Disconnect battery ground cable.
•
Loosen fuel filler cap.
• Drain fuel.
Tighten drain plug to the specified torque after
draining fuel.
~ Torque N·m (lb.ft) 20 (14)-M8
29 (22)-M14
1. Fuel tank assembly
•
See "Fuel tank removal" in this section.
2. Fuel pump (FPI assembly
• Remove FP assembly fixing screws and
remove the FP assembly.
"'\f NOTE:
• After removing FP, cover fuel tank to prevent
any dust entering.
B INSTALLATION
2. FP assembly
1. Fuel tank assembly
• See "Fuel tank installation".
• Fill the tank with fuel and tighten fuel filler
cap.
• Connect battery ground cable.
FUEL PUMP RELAY
In order to control the FP operation, the FP relay is
provided. When the starter switch is turned to "ON"
position, the FP relay operates the FP for 2 seconds.
When it is turned to "START" position, the Engine
Control Module receives the reference pulse from
the Ignition Control module and it operates the
relay, again causing the FP to feed fuel.

6E2-2 DRIVEABILITY AND EMISSIONS
DRIVEABILITV AND EMISSIONS GENERAL INFORMATION
CONTENTS
General Information
Driveability ....................... .
Emissions
........................ .
Maintenance
Schedule .............. .
Introduction ...................... .
Electronic Engine
Control .......... .
What This Section Contains ........ .
Blocking Drive Wheels
Visual/Physical
Underhood Inspection
6E2-3
6E2-3
6E2-3
6E2-3
6E2-3
6E2-3
6E2-3
6E2-3
Basic
Knowledge required . . . . . . . . . . . . 6E2-4
Basic Electric Circuits . . . . . . . . . . . . . .
6E2-4
Use
of Circuit Testing Tools . . . . . . . . . 6E2-4
Use
of Digital Volt-Ohm Meter (DVOM). 6E2-4
Diagnostic
Information . . . . . . . . . . . . . . . 6E2-4
"Check Engine" Malfunction Indicator
Lamp (MIL) . . . . . . . . . . . . . . . . . . . . 6E2-4
Intermittent "Check Engine"
Malfunction Indicator Lamp (MIL) . . 6E2-4
Reading Diagnostic
Trouble Codes . . . 6E2-5
Clearing
Trouble Codes . . . . . . . . . . . . 6E2-5
Diagnostic Test
Mode .............. 6E2-5
Engine Control
Module Learning
Ability . . . . . . . . . . . . . . . . . . . . . . . . 6E2-6
Field
Service Mode . . . . . . . . . . . . . . . . 6E2-6
Standard Nomenclature
for Certain
Electrical/Electronic
Components
and Systems . . . . . . . . . . . . . . . . . . . 6E2-6
Abbreviations and Glossary of Terms ..... 6E2-11
Driveability and Emissions
Section Summary ................... 6E2-12
Section .,. A"
Diagnostic Procedure Summary ...... 6E2-13
Data Link Connector
"SCAN Tools" ..... 6E2-14
Data
List (FO) ...................... 6E2-14
"SCAN Tool" Limitations and Use ...... 6E2-14
Intermittent Conditions ............ 6E2-14
"SCAN Tool" Positions ............... 6E2-14
Injector Pulse Width ............... 6E2-14
Closed Loop/Open Loop . . . . . . . . . . . .
6E2-14
Trouble Codes ................... 6E2-14
Throttle Position (TP) Sensor . . . . . . . . 6E2-14
Throttle Angle . . . . . . . . . . . . . . . . . . . 6E2-15 Heated
Oxygen
Sensor (H02S)
Vehicle Speed Sensor (VSS) ....... .
Programmable Read Only Memory ID .
Revolution
Per Minute (RPM) ...... .
Mile Per Hour (MPH) ............. .
Engine
Coolant Temperature (ECT) .. .
Intake Air Temperature (IAT)
Sensor
...................... .
Manifold Absolute Pressure (MAP) .. .
Barometric Pressure (BARO) ....... .
Exhaust Gas Recirculation
(EGR)
(ON/OFF) .................... .
Short Term (S.T.) Fuel Trim and
Long Term
(LT.) Fuel Trim ...... .
Long Term
(LT.) Fuel Trim ........ .
Idle Air Control (lAC) Counts ....... .
Desired Revolution
Per Minute ..... .
Air Conditioning (A/C) Request ..... .
Air Conditioning (A/C) Clutch ...... .
Power Steering Pressure (PSP)
Switch ...................... .
Battery Positive Voltage .......... .
Spark Advance .................. .
Start Up Engine Coolant .......... .
Engine
Speed (RPM) ............. .
Fuel Trim Enable ................ .
Air/Fuel Ratio .................. .
Induction Air Control ............. .
Section B -Driveability Symptoms ... .
Section C -Component Systems .... .
Engine
Control Module (ECM)
and
Sensors .................. .
Fuel Control System ............. .
Electric
Fuel Pump (in-tank) ....... .
Evaporative Emission
(EVAP)
Control System ................ .
Ignition Control (IC) .............. .
Exhaust Gas Recirculator
(EGR) .... .
Air Conditioning (A/C) Clutch Control .
Positive Crankcase Ventilation (PCV) .
Tools Needed
to Service the System .... .
General Specifications
............... .
Vacuum Hose Routing Diagram
........ .
6E2-15
6E2-15
6E2-15
6E2-15
6E2-15
6E2-15
6E2-15
6E2-15
6E2-15
6E2-15
6E2-15
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-16
6E2-17
6E2-17
6E2-17
6E2-17
6E2-17
6E2-17
6E2-17
6E2-17
6E2-18
6E2-21
6E2-22
~
... ...
•

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DRIVEABILITV AND EMISSIONS 6E2-3
ALL NEW ISUZU VEHICLES ARE CERTIFIED BY THE UNITED STATES ENVIRONMENTAL PROTECTION
AGENCY AS CONFORMING TO THE REQUIREMENTS OF THE REGULATIONS FOR THE CONTROL OF AIR
POLLUTION FROM NEW MOTOR VEHICLES. THIS CERTIFICATION IS CONTINGENT ON CERTAIN
ADJUSTMENTS BEING SET TO FACTORY STANDARDS. IN MOST CASES, THESE ADJUSTMENT POINTS
EITHER HAVE BEEN PERMANENTLY SEALED AND/OR MADE INACCESSIBLE TO PREVENT INDISCRIMINATE
OR ROUTINE ADJUSTMENT IN THE FIELD. FOR THIS REASON, THE FACTORY PROCEDURE FOR
TEMPORARILY REMOVING PLUGS, CAPS, ETC., FOR PURPOSES OF SERVICING THE PRODUCT, MUST BE
STRICTLY FOLLOWED AND, WHEREVER PRACTICABLE, RETURNED TO THE ORIGINAL INTENT OF THE
DESIGN.
GENERAL INFORMATION
DRIVEABILITY
The driveability diagnosis procedures apply to various
systems in current
ISUZU vehicles. The procedures
assume
that the vehicle is worked on properly at one
time and the
problem is due to time, wear, dirt or other
causes.
Start with the introduction that follows. This
will describe a systematic diagnostic procedure.
Any system disconnected during diagnosis should be
reconnected. This
includes wires, hoses, linkage, etc.
EMISSIONS
The exhaust emission control systems used on
ISUZU engines perform a specific function to lower
exhaust emissions while maintaining good fuel
economy and driveability.
MAINTENANCE SCHEDULE
Refer to the Maintenance Schedule in Section "OB"
General Information for the maintenance service that
should be performed to retain emission control
performance.
INTRODUCTION
ELECTRONIC ENGINE CONTROL
All engines have an Engine Control Module (ECM)
to control the fuel system. The ECM varies the air/
fuel ratio by controlling the fuel flow through the
injectors.
In addition, the ECM controls the ignition timing,
fuel pump, and various other systems.
It is important to review the component sections
and
wiring diagrams in this Section for specific
components
controlled by the ECM and what
systems are non-ECM controlled.
WHAT THIS SECTION CONTAINS
Each ISUZU engine has system controls to reduce
exhaust emissions
while maintaining good
driveability and fuel economy. •
This Section explains:
•
How to use the Driveability and Emission
Section
"6E2" engines.
• A brief description of systems used to
control fuel and emissions.
• Abbreviations that are used in Driveability
and Emissions.
• Special tools used to diagnosis and repair a
system.
Before checking the
system, adhere to the
following information:
BLOCKING DRIVE WHEELS
The vehicle drive wheels should always be
blocked, and parking brake firmly set, while
checking the system.
VISUAL/PHYSICAL UNDERHOOD
INSPECTION
A careful visual and physical underhood
inspection must
be performed as part of any
diagnostic procedure
or in finding the cause of an
emissions test failure. This can often lead to fixing
a
problem without further steps. Inspect all
vacuum hoses for correct routing, pinches, cuts,
or disconnections. Be sure to inspect hoses that
are
difficult to see beneath the throttle body and
common chamber.
Inspect all the wires in the
engine
compartment for correct and good
connections, burned or chaffed spots, pinched
wires, or contact with sharp edges or hot exhaust
manifolds. This visual/physical inspection is very
important. It must be done carefully and
thoroughly.