ESP JEEP CHEROKEE 1988 Service Owner's Manual
[x] Cancel search | Manufacturer: JEEP, Model Year: 1988, Model line: CHEROKEE, Model: JEEP CHEROKEE 1988Pages: 1378, PDF Size: 19.9 MB
Page 895 of 1378
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IN STR UM EN T P A N EL - S TA N DAR D
1988 J e ep C hero ke e
1988 Switches & Instrument Panels
JEEP
DESCRIPTION & OPERATION
Instrument panel is composed of speedometer housing,
tachometer and instrument cluster gauges.
FUEL GAUGE
System consists of a fuel gauge, an in-tank sending unit, and
appropriate wiring. Fuel gauge is grounded through variable resistor
of sending unit. A float attached to a slide rheostat follows fuel
level and varying resistance increases or decreases indicator reading.
TEMPERATURE GAUGE
System consists of gauge and sending unit and appropriate
wiring. The gauge is grounded through variable resistor of sending
unit. Changes in coolant temperature vary resistance in sending unit,
increasing or decreasing indication on gauge.
VOLTMETER
The voltmeter indicates regulated voltage to provide an
indication of charging system's ability to maintain battery charge.
OIL PRESSURE GAUGE
The oil pressure gauge system consists of gauge and a
variable resistance sending unit. Gauge needle, attached to bi-
metallic strip, responds to temperature changes.
REMOVAL & INSTALLATION
INSTRUMENT CLUSTER
Removal & Installation
1) Disconnect negative battery cable. On models with cruise
control, reach behind instrument cluster and disconnect speedometer
cable from speed switch. See Fig. 1.
2) On models without cruise control, raise vehicle on hoist.
Disconnect speedometer cable from transfer case (or transmission) and
at frame rail bracket. Move speedometer cable forward and upward to
provide slack. Lower vehicle.
3) On all models, remove instrument panel bezel screws and
bezel. Remove screws attaching cigarette lighter and switch housings
to instrument panel. Move housings aside.
4) Remove screws attaching cluster to instrument panel and
carefully pull cluster and speedometer toward rear of vehicle.
Disconnect wiring harness connectors.
5) Squeeze speedometer cable locking tabs and disconnect
cable from speedometer. See Fig. 1. Remove instrument cluster. To
install, reverse removal procedure.
Page 1011 of 1378
SPA R K C O NTR O L S YSTE M
1988 J e ep C hero ke e
1988 Exhaust Emission Systems
JEEP SPARK CONTROL SYSTEMS
DESCRIPTION
Jeep vehicles use spark control devices to assist ignition
system in controlling exhaust emissions. They are Spark Control
Temperature Override (CTO) valve, Non-Linear Vacuum Regulator (NLVR)\
valve, Forward Delay Valve, Reverse Delay Valve and on 4-cylinder
engines, Vacuum Spark Control Delay Valve. System application depends
upon engine size, emissions category and vehicle model.
COOLANT TEMPERATURE SENSOR (CTS)
The coolant temperature sensor is located in the intake
manifold coolant jacket. This sensor provides a voltage signal to the
Electronic Control Unit (ECU). The ECU uses this signal to determine
engine temperature. During cold engine operation, the ECU responds by
increasing ignition advance and inhibiting EGR operation.
NON-LINEAR VACUUM REGULATOR VALVE (NLVR)
NLVR valve is used on carbureted 6.0L models. This valve
supplies vacuum advance unit with a regulated combination of manifold
and carburetor ported vacuum when engine load is low and switches to
supply only carburetor ported vacuum as load increases.
Fig. 1: Non-Linear Vacuum Regulator Valve
Courtesy of Chrysler Motors.
OPERATION
Page 1014 of 1378
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STA R TE R - B O SC H/M IT S U BIS H I
1 988 J e ep C hero ke e
1988 Starters
BOSCH & MITSUBISHI
Jeep with 4.0L 6-Cyl.
DESCRIPTION
NOTE: Information on Jeep 2.5L starter not available from
manufacturer.
Bosch and Mitsubishi use a permanent magnet starter. A
planetary gear train transmits power between starter motor and pinion
shaft. The starter magnetic field is produced by 6 permanent magnets.
The Mitsubishi starter is a 12-volt unit that has the solenoid mounted
on the starter housing. See Fig. 3.
TROUBLE SHOOTING
NOTE: See the TROUBLE SHOOTING - BASIC PROCEDURES article
in the GENERAL TROUBLE SHOOTING section.
TESTING (ON VEHICLE)
AMPERAGE DRAW TEST
NOTE: Engine should be at operating temperature before performing
this test. Heavy duty oil or a tight engine will increase
starter draw amperage. Tests are performed with standard
volt-ammeter tester.
1) Connect tester and remote starter switch. Set voltmeter
selector to 16-volt position. Select function to 0-500-amp scale.
Connect voltmeter leads to corresponding polarity battery terminals.
2) Connect ammeter leads to corresponding battery terminals.
Disconnect coil wire from distributor cap and attach to ground to
prevent engine from starting.
3) Crank engine and observe exact reading on voltmeter. Stop
cranking engine. Turn tester control knob clockwise until voltmeter
reads exactly the same as when engine was cranked with remote starter
switch. Ammeter should indicate starter draw of about 150-220 amps.
STARTER RESISTANCE TEST
Use a voltmeter that will indicate tenths of a volt. Without
disconnecting any starter connections, perform the following
resistance tests:
1) Perform following tests with engine cranking and all
terminals connected. Connect a voltmeter at following locations:
* Positive lead to battery positive post and negative lead
to battery terminal on starter.
* Positive lead to starter housing and negative lead to
negative post on battery.
* Positive lead to battery negative post and negative lead
to battery cable connector on engine block.
2) Each of these 3 connections should show a voltmeter
Page 1071 of 1378
TIE ROD ENDS (INNER AND OUTER)
TRACK BARS
TRAILING ARMS
WHEEL BEARINGS, RACES AND SEALS
Wheel Alignment
WHEEL ALIGNMENT
Wheels and Tires
TIRES
VALVE STEMS
WHEEL ATTACHMENT HARDWARE
WHEELS (RIMS)
MOTORIST ASSURANCE PROGRAM (MAP)
OVERVIEW
The Motorist Assurance Program is the consumer outreach
effort of the Automotive Maintenance and Repair Association, Inc.
(AMRA). Participation in the Motorist Assurance Program is drawn from
retailers, suppliers, independent repair facilities, vehicle
manufacturers and industry associations.
Our organization's mission is to strengthen the relationship
between the consumer and the auto repair industry. We produce
materials that give motorists the information and encouragement to
take greater responsibility for their vehicles-through proper,
manufacturer-recommended, maintenance. We encourage participating
service and repair shops (including franchisees and dealers) to adopt
1) a Pledge of Assurance to their Customers and 2) the Motorist
Assurance Program Standards of Service. All participating service
providers have agreed to subscribe to this Pledge and to adhere to the
promulgated Standards of Service demonstrating to their customers that
they are serious about customer satisfaction.
These Standards of Service require that an inspection of the
vehicle's (problem) system be made and the results communicated to the\
customer according to industry standards. Given that the industry did
not have such standards, the Motorist Assurance Program successfully
promulgated industry inspection communication standards in 1994-95 for
the following systems: Exhaust, Brakes, ABS, Steering and Suspension,
Engine Maintenance and Performance, HVAC, and Electrical Systems.
Further, revisions to all of these inspection communication standards
are continually re-published. In addition to these, standards for
Drive Train and Transmissions have recently been promulgated.
Participating shops utilize these Uniform Inspection & Communication
Standards as part of the inspection process and for communicating
their findings to their customers.
The Motorist Assurance Program continues to work
cooperatively and proactively with government agencies and consumer
groups toward solutions that both benefit the customer and are
mutually acceptable to both regulators and industry. We maintain the
belief that industry must retain control over how we conduct our
business, and we must be viewed as part of the solution and not part
of the problem. Meetings with state and other government officials
(and their representatives), concerned with auto repair and/or
consumer protection, are conducted. Feedback from these sessions is
brought back to the association, and the program adjusted as needed.
To assure auto repair customers recourse if they were not
satisfied with a repair transaction, the Motorist Assurance Program
offers mediation and arbitration through MAP/BBB-CARE and other non-
Page 1097 of 1378
(1) - Require replacement of units where dents restrict shock
or strut piston rod movement. If dents don't restrict
movement, no service is suggested or required. Especially
critical on mono-tube shocks.
( 2) - This condition can lead to damage of the piston rod,
which, in turn, causes premature piston rod seal wear.
( 3) - Only required if replacing cartridge.
( 4) - CAUTION: If the strut cartridge has been replaced previously,
the oil on the strut housing may be filler oil. The
technician must identify the source of the oil.
( 5) - If noise is isolated to shock or strut, suggest
replacement.
( 6) - Although shocks or struts may have contributed to tire
cupping, an inspection is needed of the entire suspension
system. If the shock or strut is found to be contributing
to the tire cupping, require replacement.
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SPINDLES
SPINDLE INSPECTION \
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Condition Code Procedure
Attaching hardware
broken ................. A ... Require replacement of broken
part.
Attaching hardware
loose .................. A ... Require repair or replacement
of loose part.
Attaching hardware
missing ................ C .. Require replacement of missing
part.
Attaching hardware
threads damaged ........ A ... Require repair or replacement
of part with damaged threads.
Attaching hardware
threads stripped
(threads missing) ...... A ..... Require replacement of part
with stripped threads.
Bent .................... B ............ Require replacement.
Broken .................. A ............ Require replacement.
Race seat area
undersized ............. B ............ Require replacement.
Scored .................. A .. Require repair or replacement.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped (threads
missing) ............... A ............ Require replacement.
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SPRINGS - COIL, LEAF AND TORSION BAR
When springs are replaced, it is suggested, but not required,
that both springs on an axle be replaced to maintain equal height from
side to side and to provide a balanced ride and proper handling.
When variable rate springs are installed in place of
conventional coil springs, they must be installed in axle sets to
ensure proper handling, uniform ride, and proper chassis height.
Erroneous height measurements may result from: improper tire
inflation, non-standard tire or wheel size, and heavy load in vehicle
or trunk.
SPRING (COIL, LEAF AND TORSION BAR) INSPECTION
Page 1102 of 1378
piston rod movement. If dents don't restrict movement, no
service is suggested or required. Especially critical on
mono-tube dampers.
(2) - This condition can lead to damage of the piston rod,
which, in turn, causes premature piston rod seal wear.
( 3) - If noise is isolated to damper, suggest replacement.
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STEERING GEARS (EXCEPT RACK AND PINION)
If diagnosis has determined that complete disassembly is
necessary to determine the extent of the system failure, the
suggestion may be made to rebuild or replace the power steering pump.
Repair or replacement of the following components may be required, if
performed as part of a power steering pump overhaul or rebuild service
to meet a minimum rebuild standard.
STEERING GEAR (EXCEPT RACK AND PINION) INSPECTION
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Condition Code Procedure
Attaching hardware
broken ................. A .. Require replacement of broken
part.
Attaching hardware
loose .................. A .. Require repair or replacement
of loose part.
Attaching hardware
missing ................ C ......... Require replacement of
missing part.
Attaching hardware
threads damaged ........ A .. Require repair or replacement
of part with damaged threads.
Attaching hardware
threads stripped
(threads missing) ...... A .... Require replacement of part
with stripped threads.
Binding ................. A ... Require repair or replacement
Flex coupler binding .... A ... Require repair or replacement
of coupler.
Flex coupler loose ...... A ... Require repair or replacement
of coupler.
Flex coupler
missing parts .......... A ... Require repair or replacement
of coupler.
Flex coupler
soft/spongy ............ A . Require replacement of coupler.
Flex coupler torn ....... A . Require replacement of coupler.
Fluid contaminated ...... B ........ ( 1) Require flushing and
refilling of the system.
Gasket leaking .......... A ... Require repair or replacement
of gasket.
Housing leaking ......... A ............ Require replacement.
Hydraulic fittings
leaking ................ A ... Require repair or replacement
of fittings.
Inadequate power assist . A .......... ( 2) Further inspection
required.
See note below.
Lash exceeds
manufacturer's
specifications .......... B .. Require repair or replacement.
Seal leaking ............ A ... Require repair or replacement
Page 1132 of 1378
TIE ROD ENDS (INNER AND OUTER)
TRACK BARS
TRAILING ARMS
WHEEL BEARINGS, RACES AND SEALS
Wheel Alignment
WHEEL ALIGNMENT
Wheels and Tires
TIRES
VALVE STEMS
WHEEL ATTACHMENT HARDWARE
WHEELS (RIMS)
MOTORIST ASSURANCE PROGRAM (MAP)
OVERVIEW
The Motorist Assurance Program is the consumer outreach
effort of the Automotive Maintenance and Repair Association, Inc.
(AMRA). Participation in the Motorist Assurance Program is drawn from
retailers, suppliers, independent repair facilities, vehicle
manufacturers and industry associations.
Our organization's mission is to strengthen the relationship
between the consumer and the auto repair industry. We produce
materials that give motorists the information and encouragement to
take greater responsibility for their vehicles-through proper,
manufacturer-recommended, maintenance. We encourage participating
service and repair shops (including franchisees and dealers) to adopt
1) a Pledge of Assurance to their Customers and 2) the Motorist
Assurance Program Standards of Service. All participating service
providers have agreed to subscribe to this Pledge and to adhere to the
promulgated Standards of Service demonstrating to their customers that
they are serious about customer satisfaction.
These Standards of Service require that an inspection of the
vehicle's (problem) system be made and the results communicated to the\
customer according to industry standards. Given that the industry did
not have such standards, the Motorist Assurance Program successfully
promulgated industry inspection communication standards in 1994-95 for
the following systems: Exhaust, Brakes, ABS, Steering and Suspension,
Engine Maintenance and Performance, HVAC, and Electrical Systems.
Further, revisions to all of these inspection communication standards
are continually re-published. In addition to these, standards for
Drive Train and Transmissions have recently been promulgated.
Participating shops utilize these Uniform Inspection & Communication
Standards as part of the inspection process and for communicating
their findings to their customers.
The Motorist Assurance Program continues to work
cooperatively and proactively with government agencies and consumer
groups toward solutions that both benefit the customer and are
mutually acceptable to both regulators and industry. We maintain the
belief that industry must retain control over how we conduct our
business, and we must be viewed as part of the solution and not part
of the problem. Meetings with state and other government officials
(and their representatives), concerned with auto repair and/or
consumer protection, are conducted. Feedback from these sessions is
brought back to the association, and the program adjusted as needed.
To assure auto repair customers recourse if they were not
satisfied with a repair transaction, the Motorist Assurance Program
offers mediation and arbitration through MAP/BBB-CARE and other non-
Page 1158 of 1378
(1) - Require replacement of units where dents restrict shock
or strut piston rod movement. If dents don't restrict
movement, no service is suggested or required. Especially
critical on mono-tube shocks.
( 2) - This condition can lead to damage of the piston rod,
which, in turn, causes premature piston rod seal wear.
( 3) - Only required if replacing cartridge.
( 4) - CAUTION: If the strut cartridge has been replaced previously,
the oil on the strut housing may be filler oil. The
technician must identify the source of the oil.
( 5) - If noise is isolated to shock or strut, suggest
replacement.
( 6) - Although shocks or struts may have contributed to tire
cupping, an inspection is needed of the entire suspension
system. If the shock or strut is found to be contributing
to the tire cupping, require replacement.
\
\
\
\
\
\
\
SPINDLES
SPINDLE INSPECTION \
\
\
\
\
\
\
Condition Code Procedure
Attaching hardware
broken ................. A ... Require replacement of broken
part.
Attaching hardware
loose .................. A ... Require repair or replacement
of loose part.
Attaching hardware
missing ................ C .. Require replacement of missing
part.
Attaching hardware
threads damaged ........ A ... Require repair or replacement
of part with damaged threads.
Attaching hardware
threads stripped
(threads missing) ...... A ..... Require replacement of part
with stripped threads.
Bent .................... B ............ Require replacement.
Broken .................. A ............ Require replacement.
Race seat area
undersized ............. B ............ Require replacement.
Scored .................. A .. Require repair or replacement.
Threads damaged ......... A .. Require repair or replacement.
Threads stripped (threads
missing) ............... A ............ Require replacement.
\
\
\
\
\
\
\
SPRINGS - COIL, LEAF AND TORSION BAR
When springs are replaced, it is suggested, but not required,
that both springs on an axle be replaced to maintain equal height from
side to side and to provide a balanced ride and proper handling.
When variable rate springs are installed in place of
conventional coil springs, they must be installed in axle sets to
ensure proper handling, uniform ride, and proper chassis height.
Erroneous height measurements may result from: improper tire
inflation, non-standard tire or wheel size, and heavy load in vehicle
or trunk.
SPRING (COIL, LEAF AND TORSION BAR) INSPECTION
Page 1163 of 1378
piston rod movement. If dents don't restrict movement, no
service is suggested or required. Especially critical on
mono-tube dampers.
(2) - This condition can lead to damage of the piston rod,
which, in turn, causes premature piston rod seal wear.
( 3) - If noise is isolated to damper, suggest replacement.
\
\
\
\
\
\
\
STEERING GEARS (EXCEPT RACK AND PINION)
If diagnosis has determined that complete disassembly is
necessary to determine the extent of the system failure, the
suggestion may be made to rebuild or replace the power steering pump.
Repair or replacement of the following components may be required, if
performed as part of a power steering pump overhaul or rebuild service
to meet a minimum rebuild standard.
STEERING GEAR (EXCEPT RACK AND PINION) INSPECTION
\
\
\
\
\
\
\
Condition Code Procedure
Attaching hardware
broken ................. A .. Require replacement of broken
part.
Attaching hardware
loose .................. A .. Require repair or replacement
of loose part.
Attaching hardware
missing ................ C ......... Require replacement of
missing part.
Attaching hardware
threads damaged ........ A .. Require repair or replacement
of part with damaged threads.
Attaching hardware
threads stripped
(threads missing) ...... A .... Require replacement of part
with stripped threads.
Binding ................. A ... Require repair or replacement
Flex coupler binding .... A ... Require repair or replacement
of coupler.
Flex coupler loose ...... A ... Require repair or replacement
of coupler.
Flex coupler
missing parts .......... A ... Require repair or replacement
of coupler.
Flex coupler
soft/spongy ............ A . Require replacement of coupler.
Flex coupler torn ....... A . Require replacement of coupler.
Fluid contaminated ...... B ........ ( 1) Require flushing and
refilling of the system.
Gasket leaking .......... A ... Require repair or replacement
of gasket.
Housing leaking ......... A ............ Require replacement.
Hydraulic fittings
leaking ................ A ... Require repair or replacement
of fittings.
Inadequate power assist . A .......... ( 2) Further inspection
required.
See note below.
Lash exceeds
manufacturer's
specifications .......... B .. Require repair or replacement.
Seal leaking ............ A ... Require repair or replacement
Page 1268 of 1378
In certain conditions, the pitch of the exhaust gases may
sound like gear whine. At other times, it may be mistaken for a wheel
bearing rumble.
Tires, especially radial and snow, can have a high-pitched
tread whine or roar, similar to gear noise. Also, some non-standard
tires with an unusual tread construction may emit a roar or whine.
Defective CV/universal joints may cause clicking noises or
excessive driveline play that can be improperly diagnosed as drive
axle problems.
Trim and moldings also can cause a whistling or whining
noise. Ensure none of these components are causing the noise before
disassembling the drive axle.
Gear Noise
A "howling" or "whining" noise from the ring and pinion gear
can be caused by an improper gear pattern, gear damage, or improper
bearing preload. It can occur at various speeds and driving
conditions, or it can be continuous.
Before disassembling axle to diagnose and correct gear
noise, make sure that tires, exhaust, and vehicle trim have been
checked as possible causes.
Chuckle
This is a particular rattling noise that sounds like a stick
against the spokes of a spinning bicycle wheel. It occurs while
decelerating from 40 MPH and usually can be heard until vehicle comes
to a complete stop. The frequency varies with the speed of the
vehicle.
A chuckle that occurs on the driving phase is usually caused
by excessive clearance due to differential gear wear, or by a damaged
tooth on the coast side of the pinion or ring gear. Even a very small
tooth nick or a ridge on the edge of a gear tooth is enough the cause
the noise.
This condition can be corrected simply by cleaning the gear
tooth nick or ridge with a small grinding wheel. If either gear is
damaged or scored badly, the gear set must be replaced. If metal has
broken loose, the carrier and housing must be cleaned to remove
particles that could cause damage.
Knock
This is very similar to a chuckle, though it may be louder,
and occur on acceleration or deceleration. Knock can be caused by a
gear tooth that is damaged on the drive side of the ring and pinion
gears. Ring gear bolts that are hitting the carrier casting can cause
knock. Knock can also be due to excessive end play in the axle shafts.
Clunk
Clunk is a metallic noise heard when an automatic
transmission is engaged in Reverse or Drive, or when throttle is
applied or released. It is caused by backlash somewhere in the
driveline, but not necessarily in the axle. To determine whether
driveline clunk is caused by the axle, check the total axle backlash
as follows:
1) Raise vehicle on a frame or twinpost hoist so that drive
wheels are free. Clamp a bar between axle companion flange and a part
of the frame or body so that flange cannot move.
2) On conventional drive axles, lock the left wheel to keep
it from turning. On all models, turn the right wheel slowly until it
is felt to be in Drive condition. Hold a chalk marker on side of tire
about 12" from center of wheel. Turn wheel in the opposite direction
until it is again felt to be in Drive condition.
3) Measure the length of the chalk mark, which is the total