catalytic converter JEEP CHEROKEE 1988 Service User Guide
[x] Cancel search | Manufacturer: JEEP, Model Year: 1988, Model line: CHEROKEE, Model: JEEP CHEROKEE 1988Pages: 1378, PDF Size: 19.9 MB
Page 590 of 1378
Fig. 1: Oxygen Sensor Location
B. Replace Catalytic Converter
WARNING: IF TORCHES ARE USED WHEN WORKING ON THE EXHAUST SYSTEM,
DO NOT ALLOW THE FLAME NEAR THE FUEL LINES.
1. Remove and discard the nuts, bolts and gasket at the front of the
converter and the exhaust pipe clamp at the rear (see Fig. 2).
NOTE: Use penetrating oil if necessary.
Page 592 of 1378
2. Peel the label from its backing and apply it near the Vehicle
Emissions Control Information Label on the underside of the hood.
D. Complete Proof of Correction Form
1. Complete a Vehicle Emission Recall Proof of Correction Form and
supply it to the vehicle owner.
COMPLETION REPORTING AND REIMBURSEMENT
Claims for vehicles which have been serviced must be submitted on
the DIAL System Claims submitted will be used by Chrysler to record
recall service completions and provide dealer payments.
Use the following labor operation number and time allowance:
Labor
Operation Time
Number Allowance
Replace oxygen sensor and catalytic converter 25617182 0.8 Hours
Add the cost of the recall parts package plus applicable dealer
allowance to your claim.
PARTS RETURN
Removed catalytic converters must be returned to the Warranty
Material Return Center.
NOTE: See Warranty Policy and Procedure Manual, Chapter 6, Subsection
H for complete recall claim processing and material return
instructions.
VEHICLE NOT AVAILABLE
If a vehicle is not available for service for a known reason, let us
know by filling out the pre-addressed Vehicle Disposition Form portion
of the Owner Notification Form, or describe the reason on a postcard
and mail to:
Chrysler Corporation 429-10-04
P.O. Box 1919
Detroit, Michigan 48231-1919
Following the above procedures will expedite the processing of your
claim.
If you have any questions or need assistance in completing this
action, please contact your Zone Service Office.
Customer Services Field Operations
Chrysler Corporation
CUSTOMER NOTIFICATION LETTER
\
\
\
\
\
\
\
EMISSIONS RECALL TO REPLACE YOUR VEHICLE'S
OXYGEN SENSOR AND CATALYTIC CONVERTER
Dear Jeep Vehicle Owner:
Page 593 of 1378
Chrysler Corporation has determined that some 1989 and 1990 Jeep
Cherokee, Comanche and Wrangler vehicles equipped with a 2.5L engine,
may be in violation of Federal Emissions Standards.
The Problem is... The oxygen sensor and catalytic convener on your
vehicle (identified on the enclosed form), may be
susceptible to failure. This could result in
hydrocarbon (HC), carbon monoxide (CO) and oxides
of nitrogen (NOx) emission levels above the
allowable limits, which were established to protect
the public health from the dangers of air pollution.
What you must do... * Simply contact your Jeep dealer to schedule
a service appointment. Ask the dealer to hold
parts for your vehicle or order them prior to
your appointment.
* Bring the enclosed Owner Notification Form with
you to your dealer. It tells the dealer what
service is required for your vehicle.
What Chrysler and Chrysler will repair your vehicle free of charge
your dealer will do... (parts and labor). To do this, your dealer will
replace the oxygen sensor and catalytic
converter. The service will take about one hour
but additional time may be required depending on
how service work is scheduled and processed.
If you need help... If you have trouble getting your vehicle
repaired, please call the Chrysler Customer
Center, toll free, at 1-800-853-1403.
A representative will assist you in getting your
vehicle repaired. If you are still unable to
obtain the repair as described in this letter
within a reasonable time, you may also contact
the Manufacturers Operations Division of the
Environmental Protection Agency (6405J), 401 M
Street, S.W., Washington, D.C. 20460.
In order to ensure your full protection under the emission warranty
made applicable to your vehicle under Federal law, and your right to
participate in future recalls, it is recommended that you have your
vehicle serviced as soon as possible. Failure to do so could legally
be determined to be a lack of proper maintenance of your vehicle.
Further, without this repair your vehicle may fail a state or local
emission inspection test.
We're sorry for any inconvenience, but trust that you understand our
interest in clean air and your continuing satisfaction with our
product. Thanks for your attention to this important matter.
Customer Services Field Operations
Chrysler Corporation
Page 594 of 1378
EM IS SIO NS S TA N DAR DS
1988 J e ep C hero ke e
1988 EMISSION & TUNE-UP STANDARDS
MANUFACTURING STANDARDS
Federal and state governments have established air quality
standard during the past 20 years. Automobile manufacturers design
their vehicles to conform to standards where the vehicle will be sold
and operated. These standards cover carbon monoxide (CO), hydrocarbons\
(HC) and oxides of nitrogen (NOx).
Federal and California Standards which must be met by
manufacturers are specified in units easily measured in a testing
laboratory. Since 1970, these standards have been in "grams per mile".
This means no vehicle, whether 2-cylinder or V8, may emit more than a
set weight (in grams) of pollutants for each mile travelled. Since
large engines burn more fuel per mile than do small engines, they must
be "cleaner" per gallon burned if they are to meet these standards.
When manufacturers certify vehicle models prior to sale,
the vehicles are placed on a dynamometer and the exhaust gases are
collected in a bag. After the vehicle runs for a specified time, the
gases are analyzed and weighed. Engines and emission systems are
designed so the weight of emissions will be less than the specified
grams per mile standard.
Infra-red exhaust analyzers are commonly used in vehicle test
stations. The analyzer uses a test probe placed in the exhaust stream
to sample the exhaust gases, and measure the percentage of CO and the
parts per million of HC. These are not the same units used by the
manufacturer when the vehicle is certified. The NOx emissions cannot
be measured by an infra-red exhaust analyzer. Laboratory equipment
must be used to determine NOx emissions.
TUNE-UP STANDARDS
The technician must use the proper specifications when
adjusting the vehicle during a tune-up. The first few years of
emission-regulated vehicles were adjusted using an exhaust gas
analyzer which measured CO and HC.
In the past few years, manufacturers have produced much
cleaner running vehicles. The CO (percentage) and HC (ppm) have beco\
me
very low, especially when measured downstream of catalytic converter.
It has become difficult to measure the effect of fuel and ignition
adjustments.
One solution to this problem for vehicles using carburetors
requires the use of artificially-enriched propane adjustments. The
added propane increases or decreases engine RPM for evaluation of
carburetor rich/lean setting. This allows the technician to check
carburetor setting quickly and accurately.
As computer-controlled systems were developed, it became
possible for the vehicles to adjust the air/fuel ratio, ignition
timing and emission control device operation throughout the entire
driving range. These computer control systems use a variety of sensors
that provide the electronic control unit with information on vehicle
speed, altitude of vehicle operation and transmission gear position,
along with engine operating conditions.
Fuel delivery to achieve a lean air/fuel ratio is controlled
by the computer. The computer controls the on/off (duty cycle) time of\
the fuel injector(s) or carburetor mixture control solenoid to achieve\
leanest possible air/fuel ratio while maintaining good driveability.
Although most repair shops have exhaust gas analyzers,
computer-controlled vehicles normally do not have a CO and HC
Page 761 of 1378
\003
* E XH AU ST S YSTE M U NIF O RM IN SPEC TIO N G UID ELIN ES *
1 988 J e ep C hero ke e
GENERAL INFORMATION
Exhaust Systems Motorist Assurance Program
Standards For Automotive Repair
All Makes and Models
INTRODUCTION TO MOTORIST ASSURANCE PROGRAM (MAP)
CONTENTS
Motorist Assurance Program (MAP)
OVERVIEW OF MOTORIST ASSURANCE PROGRAM
OVERVIEW OF SERVICE REQUIREMENTS AND SUGGESTIONS
Exhaust
CATALYTIC CONVERTERS
EXHAUST AND TAIL PIPES
EXHAUST CONNECTIONS
HANGERS
HEAT RISERS (MECHANICAL EFE DEVICES)
HEAT SHIELDS
MANIFOLDS (CAST AND TUBE TYPE)
MECHANICAL EFE DEVICES
MUFFLERS AND RESONATORS
INTRODUCTION TO MOTORIST ASSURANCE PROGRAM (MAP)
OVERVIEW OF MOTORIST ASSURANCE PROGRAM
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
Page 764 of 1378
1 - Part is close to the end of its useful life (just above
discard specifications, or weak; failure likely to occur
soon, etc.)
2 - To address a customer need, convenience, or request (to
stiffen ride, enhance performance, eliminate noise,
etc.)
3 - To comply with maintenance recommended by the vehicle's
Original Equipment Manufacturer (OEM)
4 - Technician's recommendation based on substantial and
informed experience
NOTE: Suggested services are always optional. When presenting
suggested repairs to the customer, you must present
the facts, allowing the customer to draw their own
conclusions and make an informed decision about how to
proceed.
EXHAUST
SERVICE PROCEDURES REQUIRED AND SUGGESTED FOR PROPER
VEHICLE OPERATION
WARNING: Federal EPA rules prohibit altering an exhaust system in
any way that defeats the emission reduction components of a
vehicle. Be sure to review and adhere to EPA policy on
removing and replacing catalytic converters. Where state or
local laws are stricter, they take precedence over these
guidelines.
NOTE: Some exhaust systems are of a welded design. It is not
required that the entire system be replaced. Determine the
need to replace individual components based on conditions of
component.
CATALYTIC CONVERTERS
CAUTION: Before working on an exhaust system, review EPA
regulations on removing and replacing catalytic converters.
NOTE: Any time a converter has failed, further diagnosis is
required to determine the reason(s) for converter failure.
CATALYTIC CONVERTER INSPECTION
\
\
\
\
\
\
\
Condition Code Procedure
Air injection tube
broken ................. A ... Require repair or replacement
of injection tube or
replacement of catalytic
converter.
Air injection tube
burnt .................. A ... Require repair or replacement
of injection tube or
replacement of catalytic
converter.
Air injection tube
leaking ................ A ... Require repair or replacement
of injection tube or
replacement of catalytic
converter.
Air injection tube
Page 765 of 1378
loose .................. A ... Require repair or replacement
of injection tube or
replacement of catalytic
converter.
Air injection tube
restricted ............. A ... Require repair or replacement
of injection tube or
replacement of catalytic
converter.
Air injection tube
threads damaged ........ A ... Require repair or replacement
of injection tube or
replacement of catalytic
converter.
Air injection tube
threads stripped
(threads missing) ...... A ... Require repair or replacement
of injection tube or
replacement of catalytic
converter.
Body cracked ............ B .. Require repair or replacement.
Converter empty ......... A .. Require repair or replacement.
Converter fill plug
missing ................ C .. Require repair or replacement.
Converter missing ....... C ............ Require replacement.
Exhaust gases leaking ... A .. Require repair or replacement.
Flanges leaking ......... A ... Require repair or replacement
of flanges.
Inlet pipes cracked ..... B .. Require repair or replacement.
Internal rattle (except
pellet-type) ........... 2 .......... (1) Further inspection
required.
Mounting brackets that
are part of converter
broken ................. A .. Require repair or replacement.
Obvious overheating ..... .. ......... ( 2) Require testing of
converter.
Outlet pipes cracked .... B .. Require repair or replacement.
Pieces of catalyst
material found
downstream ............. 1 ............ Suggest replacement.
Plugged ................. A ........ ( 3) Require replacement.
Testing has determined
that existing converter
has been lead-poisoned,
contaminated, or failed
testing ................ A .. Require repair or replacement.
( 1) - If the converter is breaking up, suggest converter
replacement. If an object has fallen into the converter,
remove the object.
( 2) - Overheating is caused by something other than the
converter. Further diagnosis is required to determine
the cause of the overheating.
( 3) - Determine cause and correct to ensure that new converter
will not become plugged.
\
\
\
\
\
\
\
EXHAUST AND TAIL PIPES
NOTE: For pipes with resonators, also see MUFFLERS AND RESONATORS.
EXHAUST AND TAIL PIPE INSPECTION
Page 918 of 1378
whichever occurs first.
EMISSION DEFECT WARRANTY (EXCEPT CALIFORNIA)
It warrants that vehicle meets Federal emissions standards in
force at time of vehicle's manufacture. Warranty covers the cost of
repair or adjustment of any parts of vehicle's emission control
systems that are defective in material, workmanship or factory
preparation, but ONLY IF the defect causes the vehicle to fail to meet
Federal standards. Begins at warranty start date and lasts for 5 years
or 50,000 miles, whichever occurs first.
EMISSION PERFORMANCE WARRANTY (EXCEPT CALIFORNIA)
It begins at warranty start date and lasts for 5 years or 50,
000 miles, whichever comes first. This warranty applies only under the
following conditions:
* Vehicle failed a Federally-approved state or local emissions
test.
* Vehicle has been maintained and operated properly up until
the time of testing.
* Owner faces a penalty or other sanctions because of the
vehicle's failure to pass the local emissions test.
The following components and systems are covered: Carburetor
Feedback Control System, Electronic Fuel Injection System, Air Cleaner
Vapor Containment Door System, Electronic Spark Control, Electronic
Control Module, Vapor Storage Canister and Controls, Deceleration
Throttle Control, EGR Valve & Control System, Air Pump, Belt & Pulley,
Air Injection Controls, PCV Valve, Catalytic Converter, Vacuum Hoses,
Clamps, Fittings & Tubing used in these components and systems,
Vacuum, Temperature, Altitude, Speed and Time-Sensitive Valves and
Switches used in these components and systems.
EMISSION PERFORMANCE WARRANTY (CALIFORNIA)
If vehicle fails a Smog Check inspection, all necessary
repairs and adjustments will be made by manufacturer to ensure that
your vehicle passes the inspection. Warranty begins at warranty start
date and lasts for a period of 3 years or 50,000 miles, whichever
occurs first.
EMISSION DEFECTS WARRANTY (CALIFORNIA)
If any emission-related part on your vehicle is defective,
the part will be repaired or replaced by manufacturer for a period of
3 years or 50,000 miles, whichever occurs first. Warranty begins at
warranty start date and lasts for a period of 3 years or 50,000 miles,
whichever occurs first.
The following emission-related parts are warranted for 7
years or 70,000 miles, whichever occurs first, and will be repaired or
replaced by manufacturer if found to be defective in material or
workmanship: Catalytic Converter, Intake Manifold, Carburetor,
Throttle Body, Injectors, Fuel Tank, Exhaust Manifolds (4.0L).
FUSES & CIRCUIT BREAKERS
Fuse panel is located at the lower left side of dash on most
models.
Page 951 of 1378
computers may lose memory data. When battery power is
restored, driveability problems may exist on some vehicles.
These vehicles may require a relearn procedure. See COMPUTER
RELEARN PROCEDURES article in GENERAL INFORMATION section.
REPLACING BLOWN FUSES
Before replacing a blown fuse, remove ignition key, turn off
all lights and accessories to avoid damaging the electrical system. Be
sure to use fuse with the correct indicated amperage rating. The use
of an incorrect amperage rating fuse may result in a dangerous
electrical system overload.
BRAKE PAD WEAR INDICATOR
Indicator will cause a squealing or scraping noise, warning
that brake pads need replacement.
BRAKE WARNING LIGHT
CAUTION: If BRAKE warning light is on with parking brake disengaged
and engine running, there may be a problem in the hydraulic
brake system. Braking effort, brake pedal travel and
stopping distances may increase.
CATALYTIC CONVERTER
To prevent catalytic converter overheating, DO NOT allow
engine to idle for more than 20 minutes.
COMMAND-TRAC (4WD)
CAUTION: NEVER operate a Command-Trac vehicle in 4WD on dry,
hard-surfaced roads for a sustained period. Use 4L only
when needed for added pulling power. Operating vehicle in
4WD mode on such roads will cause stress and possible
damage to components, as well as make shifting difficult.
To reduce shifting effort, drive vehicle in Reverse for a
few feet, or drive off hard-surfaced road momentarily to
allow tire slippage.
FRONT AND REAR DIFFERENTIALS (4WD)
CAUTION: DO NOT use water, steam, kerosene or gasoline for flushing
a differential. ONLY use a flushing oil.
TRAC-LOK DIFFERENTIALS (4WD)
CAUTION: DO NOT flush a rear axle Trac-Lok differential. Trac-Lok
differentials may be cleaned only by disassembling the
unit and wiping the components with clean, lint-free cloth.
CAUTION: NEVER attempt to engage Low range when vehicle is moving
faster than 2-3 MPH, as transfer case damage may result.
GASOLINE CONTAINING ALCOHOL
CAUTION: Exclusive use of gasohol is not recommended. Vehicle test
results have shown that significant fuel system corrosion
can result when gasohol is used exclusively.
Page 1285 of 1378
\003
TU NE-U P - 4 -C YL
1988 J e ep C hero ke e
1988 Jeep 4 Tune-Up
TUNE-UP
All Models
IDENTIFICATION
ENGINE IDENTIFICATION
Engine can be identified by the 4th character of the Vehicle
Identification Number (VIN). The VIN is stamped on a plate attached to\
top left corner of instrument panel.
ENGINE CODES
\
\
\
\
\
\
\
Engine Code
2.5L (150") TBI .................................................. H\
\
\
\
\
\
\
\
TUNE-UP NOTES
NOTE: When performing tune-up procedures described in this
article, the following notes and precautions must be
followed.
Due to late changes and corrections, always refer to Emission
Control Label in engine compartment before attempting tune-up. If
manual and label differ, always use label specifications.
EPA High Altitude emission standards apply to vehicles sold
in certain areas outside California which have an elevation above 4000
feet.
When performing tune-up on vehicles equipped with catalytic
converter, do not allow or create an engine misfire in one or more
cylinders for an extended period of time. Damage to converter may
occur due to loading converter with unburned fuel.
TESTING
ENGINE COMPRESSION
Test compression with all spark plugs removed, throttle
plates and choke valve wide open and engine at normal operating
temperature. Crank engine through at least 5 compression strokes
before recording reading.
COMPRESSION SPECIFICATIONS
\
\
\
\
\
\
\
Application Specification
Compression Ratio ............................................ 9.2:1
Compression Pressure ................ 155-185 psi (10.9-13.0 kg/cm
)
Max. Variation Between Cylinders ............... 30 psi (2.1 kg/cm) \
\
\
\
\
\
\
SPARK PLUGS
SPARK PLUG TYPE