maintenance schedule ISUZU KB P190 2007 Workshop Repair Manual

GENERAL INFORMATION 0A-3
NOTES ON THE FORMAT OF THIS MANUAL
1. Find the applicable section by referring to the index at the front of the W orkshop Manual binder.
2. The following technical service information is included in this Section: • Identification
• Maintenance schedules
• Recommended Iubricants
• Recommended fuels
• Oil viscosity charts
3. Individual sections of this W orkshop Manual are divided into the following categories: • Main data and specifications
• Torque specifications
• Recommended liquid gasket
• Loctite application procedure
• Servicing
• Removal and installation
• Disassembly
• Inspection and repair
• Reassembly
• Troubleshooting
4. Each "Major Components" page of this W orkshop Manual has an exploded view of the applicable area.
A brief explanation of the notation used follows:



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ISUZU KB P190 2007

MAINTENANCE AND LUBRICATION 0B-1
SECTION 0B
MAINTENANCE AND LUBRICATION
TABLE OF CONTENTS
PAGE
Maintenance Schedule (For GENERAL EXPORT)......................................................... 0B- 2
Maintenance Schedule (For EUROPE)........................................................................... 0B- 5
Severe Conditions Maintenance Schedule (For GENERAL EXPORT) ........................ 0B- 9
Severe Conditions Maintenance Schedule (For EUROPE) .......................................... 0B-10
Recommended Fluids and Lubricants (For GENERAL EXPORT) ............................... 0B-11
Recommended Fluids and Lubricants (For EUROPE) ................................................. 0B-13
Oil Viscosity Chart........................................................................................................... 0B-14


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0B-2 MAINTENANCE AND LUBRICATION
MAINTENANCE SCHEDULE (For GENERAL EXPORT)
Items followed by an asterisk (*) require more frequent maintenance if the vehicle is driven under severe conditions.
Replace the fuel filter (**Mark) when the fuel filter indicator light is lit.
Refer to "SEVERE CONDITIONS MAINTENANCE SCHEDULE."

I : Inspect and correct or replace as necessary A : Adjust
R : Replace or change T : Tighten to specified torque L : Lubricate


SERVICE INTERVAL: × 1,000 km 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100(Use odometer reading × 1,000 miles 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60or months whichever
comes first)
or months 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120
ENGINE
Idling speed and acceleration
(GASOLINE) I I - I - I - I - I - I - I - I - I - I (DIESEL) I I I I I I I I I I I I I I I I I I I I * Air cleaner element
(GASOLINE) - I - I - I - R - I - I - I - R - I - I (DIESEL) I I I I I I I R I I I I I I I R I I I I * Engine oil (HFV6) - - R - - R - - R - - R - - R - - R - - (C24SE) Replace every 12,000km (4JH1-TC, 4JJ1 (Standard Output),
4JJ1 (High Output)) - R - R - R - R - R - R - R - R - R - R

(4JA1-T) R R R R R R R R R R R R R R R R R R R R * Engine oil filter (HFV6) - - R - - R - - R - - R - - R - - R - - (C24SE) Replace every 12,000km (4JH1-TC, 4JA1-T) - R - R - R - R - R - R - R - R - R - R (4JJ1 (Standard Output),
4JJ1 (High Output)) - - - R - - - R - - - R - - - R - - - R
Oil leakage and contamination (GASOLINE) - I - I - I - I - I - I - I - I - I - I (DIESEL) I I I I I I I I I I I I I I I I I I I I Fuel leakage
I I - I - I - I - I - I - I - I - I - I Fuel tank - - - I - - - I - - - I - - - I - - - I O2 Sensor (C24SE) Replace every 160,000km (HFV6)
MIL diagnostic Indicates O2 Sensor Valve clearances (6VE1) Check and adjust if noisy (4JH1-TC, 4JA1-T) A - - A - - - A - - - A - - - A - - - A (4JJ1 (Standard Output),
4JJ1 (High Output)) - - - - - - - A - - - - - - - A - - - -
Spark plugs (C24SE) (for leaded fuel
use) - R - R - R - R - R - R - R - R - R - R
Spark plugs (C24SE) (for unleaded
fuel use) - - - - - R - - - - - R - - - - - R - -
Spark plugs
(HFV6) Replace every 120,000km Spark plug wire - - - - - - - - - - - - - - - - - - - I Fuel filter (GASOLINE) - - - R - - - R - - - R - - - R - - - R (4JH1-TC, 4JA1-T) - - R - - R - - R - - R - - R - - R - - ** (4JJ1 (Standard Output),
4JJ1 (High Output)) Replace the fuel filter when the fuel filter indicator light is lit.
Fuel pump in fuel tank
(4JJ1 (Standard Output),
4JJ1 (High Output)) - - - - - - - I - - - - - - - I - - - -
Engine / Accessory drive belt
(C24SE) - - - - - - - - - I - - - - - - - - - I

(HFV6) Replace every 100,000km Fan belt tension and damage
(DIESEL) I I I I I I I I I I I I I I I I I I I I
* Exhaust system
I I - I - I - I - I - I - I - I - I - I Engine coolant concentration (HFV6) - I - I - I - I - I - I - I - I - I - R (C24SE) - I - I - I - I - R - I - I - I - I - R (DESEL) - I - I - I - I - I - I - I - I - I - I Engine coolant
(4JJ1 (Standard Output),
4JJ1 (High Output)) Change every 2 years
Cooling system for water leakage - I - I - I - I - I - I - I - I - I - I All hoses and pipes in engine
compartment for clogs or damage - I - I - I - I - I - I - I - I - I - I
Timing belt
(C24SE) - - - - - - - - - - - - - - - I - - - - Replace every 120,000km Timing belt (6VE1) Replace every 160,000km

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MAINTENANCE AND LUBRICATION 0B-5
MAINTENANCE SCHEDULE (For EUROPE)
Items followed by an asterisk (*) require more frequent maintenance if the vehicle is driven under severe conditions.
Replace the fuel filter (**Mark) when the fuel filter indicator light is lit.
Refer to "SEVERE CONDITIONS MAINTENANCE SCHEDULE."
Diesel Engine model (ACEA B2 specification engine oil)

I : Inspect and correct or replace as necessary A : Adjust
R : Replace or change T : Tighten to specified torque L : Lubricate

SERVICE INTERVAL: × 1,000 km 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
(Use odometer reading or × 1,000 miles 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60
months whichever comes
first)
or months 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120
DIESEL ENGINE * Engine oil - R - R - R - R - R - R - R - R - R - R* Engine oil filter - - - R - - - R - - - R - - - R - - - ROil leakage and contamination I I I I I I I I I I I I I I I I I I I I Idling speed and acceleration I I I I I I I I I I I I I I I I I I I I Fan belt tension and damage I I I I I I I I I I I I I I I I I I I I Exhaust system I I - I - I - I - I - I - I - I - I - I All hoses and pipes in engine
compartment for clog of damage - I I I I I I I I I I I I I I I I I I I
Valve clearance
- - - A - - - A - - - A - - - A - - - A * Air cleaner element I I I I I I I R I I I I I I I R I I I I ** Fuel filter Replace the fuel filter when the fuel filter indicator light is lit. Engine coolant concentration - I - I - I - I - I - I - I - I - I - I Cooling system for water leakage - I - I - I - I - I - I - I - I - I - I CLUTCH Clutch fluid I I - I - I - I - I - I - I - I - I - I Clutch pedal travel and play I I - I - I - I - I - I - I - I - I - I TRANSMISSION OR TRANSMISSION
W ITH TRANSFER CASE

* Manual transmission with fluid - R - I - - - R - - - I - - - R - - - I * Transfer case oil (MT) - - - I - - - I - - - I - - - I - - - I Oil leakage I I I I I I I I I I I I I I I I I I I I Gear control mechanism for
looseness - - - I - - - I - - - I - - - I - - - I
* Automatic transmission fluid - - - I - - - I - - - I - - - I - - - I * Transfer case oil (AT)
- - - I - - - - - - - I - - - - - - - I PROPELLER SHAFT Loose connections - I - I - I - I - I - I - I - I - I - I * Universal joints and splines for wear - I - I - I - I - I - I - I - I - I - I Universal joints and sliding sleeve (4W D) - L - L - L - L - L - L - L - L - L - L
FRONT AND REAR AXLE * Differential gear oil (Front and rear) - R - I - - - R - - - I - - - R - - - I Oil leakage I I I I I I I I I I I I I I I I I I I I Shift on the fly system gear oil I - - I - - - I - - - I - - - I - - - I
Front axle shaft boot for damage - - - I - - - I - - - I - - - I - - - I Axle case for distortion or damage - - - I - - - I - - - I - - - I - - - I Axle shafts for distortion or damage - - - I - - - I - - - I - - - I - - - I

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ISUZU KB P190 2007

MAINTENANCE AND LUBRICATION 0B-9
SEVERE CONDITIONS MAINTENANCE SCHEDULE (For GENERAL EXPORT)

Severe driving conditions
A : Repeated short trips
C24SE : C24SE Gasoline engine
B : Driving on rough roads
HFV6 : HFV6 Gasoline engine
C : Driving on dusty roads
G : Gasoline engine
D : Driving in extremely cold weather and/or on salted roads
4JA1-T : 4JA1-T Diesel engine
E : Towing trailer or climbing mountain frequently
4JH1-TC : 4JH1-TC Diesel engine
F : Operation in high ambient temperature conditions
4JJ1 (Standard Output):
4JJ1 Standard Output Diesel engine

4JJ1 (High Output): 4JJ1 High Output Diesel engine

D : Diesel engine

MT : Manual transmission

AT : Automatic transmission

4W D : Four wheel drive


Condition
A B C D E F A+D
Engine oil G : Change every 5,000 km (3,000 miles) or 3 month
4JA1-T : Change every 2,500 km (1,500 miles) 4JH1-TC 4JJ1 (Standard Output) 4JJ1 (High Output):

Change every 5,000 km (3,000 miles)




Engine oil filter G : Replace every 5,000 km (3,000 miles) or 3 monthD : Replace every 5,000 km (3,000 miles)



Exhaust pipes and mounting Inspect every 5,000 km (3,000 miles)





Air cleaner element
Replace every 20,000 km (12,000 miles) D : Inspect every 2,500 km (1,500 miles)


Steering system for looseness
or damage Inspect every 5,000 km (3,000 miles)


Universal joints and sleeves Inspect for wear and lubricate every 5,000 km (3,000 miles)




Transmission or transmission
with transfer case oil MTC24SE D Change every 20,000 km (12,000 miles)
after changing at initial 10,000 km (6,000 miles)
MT HFV6 Change every 40,000 km (24,000 miles)

AT Transmission:
Change every 20,000 km (12,000 miles)








4W D Transfer:
Change every 20,000 km (12,000 miles)


Differential oil
Change every 20,000 km (12,000 miles)
after changing at initial 10,000 km (6,000 miles)


Front brake pads and di
scs
wear Inspect every 5,000 km (3,000 miles)




Rear brake lining and drum
wear Inspect every 5,000 km (3,000 miles)





Interval
Item

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0B-10 MAINTENANCE AND LUBRICATION
SEVERE CONDITIONS MAINTENANCE SCHEDULE (For EUROPE)

Severe driving conditions
MT : Manual transmission
A: Repeated short trips
AT : Automatic transmission
B: Driving on rough roads
4W D : Four wheel drive
C: Driving on dusty roads
D: Driving in extremely cold weather and/or on salted roads
E: Towing trailer or climbing mountein frequently

Condition
Item Interval A B C D E A+D
Engine oil Change every 5,000 km (3,000 miles)





Engine oil filter Replace every 5,000 km (3,000 miles)





Exhaust pipes and mounting Inspect every 10,000 km (6,000 miles)





Air cleaner element
Replace every 20,000 km (12,000 miles)



Steering system for looseness or
damage Inspect every 5,000 km (3,000 miles)


Universal joints and sleeves Inspect for wear and lubricate every 10,000 km (6,000 miles)




Transmission or transmission
with transfer case oil MT Change every 30,000 km (18,000 miles)
after changing at initial 10,000 km (6,000 miles)


AT
Transmission:
Inspection every 20,000 km (12,000 miles)







4W D Transfer:
Change every 30,000 km (18,000 miles)
After changing at initial 10,000 km (6,000 miles)


Differential oil
Change every 20,000 km (12,000 miles)
after changing at initial 10,000 km (6,000 miles)


Front brake pads and di
scs wear Inspect every 5, 000 km (3,000 miles)




Rear brake lining and drum wear Inspect every 5,000 km (3,000 miles)







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MAINTENANCE AND LUBRICATION 0B-11
Recommended Fluids and Lubricants (For GENERAL EXPORT)
In order to obtain maximum performance and longest service life from your ISUZU vehicles, it is very important to
select and use correctly the best lubricants and diesel fuels.
W hen lubricating, be sure to use ISUZU genuine lubricants or recommended lubricants listed below, according to
the maintenance schedule for each vehicle model.
The lubrication intervals in the maintenance schedule and coverage and period of new vehicle warranty are based
on the use of ISUZU genuine lubricants or recommended lubricants listed in the chart, which will serve as a guide
for selecting lubricants of the correct brand name.

GRADE
LUBRICATION MAKE BRAND/TYPE API ACEA JASO
Gasoline engine
crankcase C24SE
ISUZU GENUINE
ISUZU GENUINE
CALTEX
SHELL
ELF
TOTAL
CASTROL
BP BESCO RACING ACE TYPE SJ (5W-30)
BESCO MULTI ACE (7.5W-30)
HAVOLINE FORMULA (15W-40, 10W-30, 20W-50) HELIX PLUS (15W-50)
SUPER SPORTI S (15W-40)
QUARTZ 5000 (15W-40, 20W-50)
GTX-7 (15W-40)
VISCO 3000 (15W-40) SJ
SG SL
SJ/CF SG
SJ/CF
SG/SH
SG/SH


A3/B3
A2/B2


Gasoline engine
crankcase HFV6

CALTEX 10W-30

HAVOLINE FORMULA (10W-30) SL
SL
Diesel engine crankcase
ISUZU GENUINE
ISUZU GENUINE
ISUZU GENUINE
CALTEX/CHEVRON
CALTEX/CHEVRON
SHELL
SHELL
ELF
TOTAL
CASTROL
CASTROL
BP BESCO MULTI-Z TYPE CF-4 (10W-30)
BESCO MULTI-Z SUV (5W-30)
BESCO S-3 (10W, 20W, 30, 40)
DELO CXJ (15W-40, 20W-50, 40)
DELO 400 MULTIGRADE (15W-40)
RIMULA X (15W-40)
RIMULA D (15W-40, 30, 40)
PERFO 3F (15W-40)
RUBIA XT (15W-40)
RX SUPER PLUS (15W-40)
TECTION J PLUS (15W-40)
BP VANELLUS C6 (15W-40) CF-4
CD
CD
CD/CF
CD/CE/CF/CI-4 CH-4
CD/CF
CF-4/CE CF-4
CH-4
CH-4
CH-4



E3/E5 E3
B2/E2 E2
E3
E3/B3 E3


DH-1
DH-1
DH-1



DH-1
Manual transmission
C24SE D
Transfer case
ISUZU GENUINE
CALTEX/CHEVRON
SHELL
ELF
TOTAL
CASTROL
BP

BESCO GEAR OIL TRANSAXLE (5W-30)
DELO 400 MULTIGRADE (15W-40)
HELIX PLUS (15W-50)
SUPER SPORTI (15W-40)
QUARTZ 5000 (15W-40, 20W-50)
RX SUPER PLUS (15W-40)
BP VANELLUS C6 (15W-40)

SG CD/CE/CF/CI-4 SJ/CF
SG/CD SJ/CF
CD/CE/CF
CD/CE/CF


E3/E5
A3/B3
A2/B2

DH-1




Manual transmission
HFV6
MOBIL 75W-90
MOBIL XHP (75W-90) GL-3



Differential
Shift on the fly system
(GL-5 only) ISUZU GENUINE
ISUZU GENUINE
CALTEX
SHELL
ELF
TOTAL
CASTROL
CASTROL
BP
BP BESCO GEAR OIL SH (80W-90, 90, 140)
BESCO SHIFT ON THE FLY (75W-90)
THURBAN GL-5 EP (80W-90, 85W-140)
SPIRAX A (140)
TRANSELF TYPE B (80W-90, 85W-140)
TRANSMISSION TM (80W-90, 85W-140)
EPX90 (90)
DYNA DRIVE (80W-90)
ENERGEAR HYPO (90)
ENERGEAR EP (80W-90) GL-5
GL-5 GL-5
GL-5
GL-5
GL-5
GL-5
GL-5
GL-5
GL-5


Differential
(Limited Slip Differential) ISUZU GENUINE
CALTEX
SELL
ELF
TOTAL
CASTROL
BP BESCO GEAR OIL LSD (140)
GEAR OIL LSD (90)
SPIRAX A LS 90 (90)
TRANSELF TYPE BLS (90)
TRANSMISSION DA (85W-90)
HYPOY LSX (90)
ENERGEAR LS-M (90) GL-5
GL-5
GL-5
GL-5
GL-5
GL-5
GL-5
Automatic transmission
4JH1-TC 4JJ1 (Standard Output)
Power steering
ISUZU GENUINE
CALTEX/TEXACO
SHELL
ELF
TOTAL
CASTROL
BP BESCO ATF III
TEXAMATIC 1888 (DEXRON  III)
SHELL DONAX TG (DEXRON  III)
ELFMATIC G3 (DEXRON  III)
TOTAL FLUID AT42 (DEXRON  III)
TQ DEXRON III (DEXRON  III)
AUTORAN DX3 (DEXRON  III)






Automatic transmission
4JJ1 (High Output)
EXXON MOBIL
MOBIL ATF 3309

Automatic transmission
HFV6
DEXRON III

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ISUZU KB P190 2007

MAINTENANCE AND LUBRICATION 0B-13
RECOMMENDED FLUIDS AND LUBRICANTS (For EUROPE)


In order to obtain maximum performance and longest service life from your ISUZU vehicles, it is very important to
select and use correctly the best lubricants and diesel fuels.
W hen lubricating, be sure to use ISUZU genuine lubricants or recommended lubricants listed below, according to
the maintenance schedule for each vehicle model.

LUBRICATION/FLUID GRADE
API ACEA OTHER
Diesel engine crankcase B2/B3
E2/E3
Manual transmission
Transfer case B2/B3
E2/E3
Differential
Shift on the fly system
(GL-5 only)
GL-5

BESCO GEAR OIL SH (80W-90, 90, 140) (ISUZU GENUINE)
BESCO SHIFT ON THE FLY (75W-90) (ISUZU GENUINE)
THURBAN GL-5 EP (80W-90, 85W-140) (CALTEX)
SPIRAX A (140) (SHELL)
TRANSELF TYPE B (80W-90, 85W-140) (ELF)
TRANSMISSION TM (80W-90, 85W-140) (TOTAL)
EPX90 (90)(CASTROL)
DYNA DRIVE (80W-90) (CASTROL)
ENERGEAR HYPO (90) (BP)
ENERGEAR EP (80W-90) (BP)
Differential
(Limited Slip Differential)
(GL-5 only) GL-5

BESCO GEAR OIL LSD (140) (ISUZU GENUINE)
GEAR OIL LSD (90) (CALTEX)
SPIRAX A LS 90 (90) (SHELL)
TRANSELF TYPE BLS (90) (ELF)
TRANSMISSION DA (85W-90) (TOTAL)
HYPOY LSX (90) (CASTROL)
ENERGEAR LS-M (90) (BP)
Automatic transmission MOBIL ATF 3309
Power steering

DEXRON III
Propeller shaft sliding yoke
Universal joint
(General purpose grease in
Molybdenum) NLGI #2 or #3
multi purpose type grease
containing molybdenum disulfide
Engine cooling system Good quality ethylene glycol antifreeze or GM spec.
6033-M or equivalent

NOTE:
* If GL-5 Limited Slip Differential Lubricant is not available, use GL-5 Lubricant mixed with 1 bottle (118ml) of Limited
Slip Differential Lubricant additive (Parts No. 8-01052-358-0) or equivalent.



FLUID TYPE

Clutch and brake fluid reservoir Besco brake fluid (For light duty)
Hydraulic brake fluid SAE J1703
FMVSS 116 DOT.3 grade


DIESEL FUEL/APPLICABLE STANDARD
JIS (JAPANESE INDUSTRIAL STANDARD)
DIN (DEUTSCHE INDUSTRIE NORMEN)
SAE (SOCIETY OF AUTOMOTIVE ENGINEERS)
BS (BRITISH STANDARD) Based on K2204 GAS OIL
Based on EN590: 1997L
Based on SAE J-313C
Based on BS EN590: 1997

NOTE:
Use the applicable standard or equivalent for diesel fuels.



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ISUZU KB P190 2007

6C-6 ENGINE FUEL (C24SE)
Fuel Filter
Inspection
1. Replace the fuel filter if the fuel leaks from fuel filter
body or if the fuel filter body itself is damaged.
2. Replace the filter if it is clogged with dirt o
r
sediment.
Installation
1. Install the filter to holder from fuel tank front side.
NOTE: Attend direction of fuel filter. (1) to engine side
(2) to fuel tank side.
NOTE: Verify to hang holder hook to fuel filter.






RTW 36CSH000301
2. Connect the quick connector from the fuel tube to
the fuel filter.
NOTE: Pull of the left checker into the fuel pipe.
NOTE: Refer to “Fuel Tube/Quick Connector Fittings” in
this section when performing any repairs.
3. Tighten fuel filler cap until at least one click are heard.
4. Connect the battery ground cable.
Inspection
After installation, start engine and check for fuel
leakage.
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 completel
y
submerged in the water. It is a selfcleaning type, not
requiring scheduled maintenance. Excess water and
sediment in the tank restricts fuel supply to the engine,
resulting in engine stoppage. In such a case, the tank
must be cleaned thoroughly.


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ISUZU KB P190 2007

6E–54 ENGINE DRIVEABILITY AND EMISSIONS
GENERAL DESCRIPTION FOR ELECTRIC
IGNITION SYSTEM
The engine use two ignition coils, one per two cylinders.
A two wire connector provides a battery voltage primary
supply through the ignition fuse.
The ignition control spark timing is the ECM’s method of
controlling the spark advance and the ignition dwell.
The ignition control spark advance and the ignition dwell
are calculated by the ECM using the following inputs.
• Engine speed
• Crankshaft position (CKP) sensor
• Engine coolant temperature (ECT) sensor
• Throttle position sensor
• Vehicle speed sensor
• ECM and ignition system supply voltage
Ignition coil works to generate only the secondary
voltage be receiving the primary voltage from ECM.
The primary voltage is generated at the coil driver
located in the ECM. The coil driver generate the primary
voltage based on the crankshaft position signal. In
accordance with the crankshaft position signal, ignition
coil driver determines the adequate ignition timing and
also cylinder number to ignite.
Ignition timing is determined the coolant temperature,
intake air temperature, engine speed, engine load,
knock sensor signal, etc.
Spark Plug
Although worn or dirty spark plugs may give satisfactory
operation at idling speed, they frequently fail at higher
engine speeds. Faulty spark plugs may cause poor fuel
economy, power loss, loss of speed, hard starting and
generally poor engine performance. Follow the
scheduled maintenance service recommendations to
ensure satisfactory spark plug performance. Refer to
Maintenance and Lubrication .
Normal spark plug operation will result in brown to
grayish-tan deposits appearing on the insulator portion
of the spark plug. A small amount of red-brown, yellow,
and white powdery material may also be present on the
insulator tip around the center electrode. These
deposits are normal combustion by-products of fuels
and lubricating oils with additives. Some electrode wear
will also occur. Engines which are not running properly
are often referred to as “misfiring.” This means the
ignition spark is not igniting the air/fuel mixture at the
proper time. While other ignition and fuel system causes
must also be considered, possible causes include
ignition system conditions which allow the spark voltage
to reach ground in some other manner than by jumping
across the air gap at the tip of the spark plug, leaving
the air/fuel mixture unburned. Misfiring may also occur
when the tip of the spark plug becomes overheated and
ignites the mixture before the spark jumps. This is
referred to as “pre-ignition.”
Spark plugs may also misfire due to fouling, excessive
gap, or a cracked or broken insulator. If misfiring occurs before the recommended replacement interval, locate
and correct the cause.
Carbon fouling of the spark plug is indicated by dry,
black carbon (soot) deposits on the portion of the spark
plug in the cylinder. Excessive idling and slow speeds
under light engine loads can keep the spark plug
temperatures so low that these deposits are not burned
off. Very rich fuel mixtures or poor ignition system output
may also be the cause. Refer to DTC P1167.
Oil fouling of the spark plug is indicated by wet oily
deposits on the portion of the spark plug in the cylinder,
usually with little electrode wear. This may be caused by
oil during break-in of new or newly overhauled engines.
Deposit fouling of the spark plug occurs when the
normal red-brown, yellow or white deposits of
combustion by-products become sufficient to cause
misfiring. In some cases, these deposits may melt and
form a shiny glaze on the insulator around the center
electrode. If the fouling is found in only one or two
cylinders, valve stem clearances or intake valve seals
may be allowing excess lubricating oil to enter the
cylinder, particularly if the deposits are heavier on the
side of the spark plug facing the intake valve.
Excessive gap means that the air space between the
center and the side electrodes at the bottom of the
spark plug is too wide for consistent firing. This may be
due to improper gap adjustment or to excessive wear of
the electrode during use. A check of the gap size and
comparison to the gap specified for the vehicle in
Maintenance and Lubrication will tell if the gap is too
wide. A spark plug gap that is too small may cause an
unstable idle condition. Excessive gap wear can be an
indication of continuous operation at high speeds or
with engine loads, causing the spark to run too hot.
Another possible cause is an excessively lean fuel
mixture.

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ISUZU KB P190 2007