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1993 Jeep Cherokee

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 organizations 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 vehicles (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 non­profit organizations. MAP conducted pilot programs in twelve states before announcing the program nationally in October, 1998. During the pilots, participating repair shops demonstrated their adherence to the Pledge and Standards and agreed to follow the UICS in communicating the results of their inspection to their customers. To put some "teeth" in the program, an accreditation requirement for shops was initiated. The requirements are stringent, and a self-policing method has been incorporated which includes the "mystery shopping" of outlets.

We welcome you to join us as we continue our outreach... with your support, both the automotive repair industry and your customers will reap the benefits. Please visit MAP at our Internet site www. motorist.org or contact us at:

1444 I Street, NW Suite 700

Washington, DC 20005

Phone (202) 712-9042 Fax (202) 216-9646 January 1999

MAP UNIFORM INSPECTION GENERAL GUIDELINES

OVERVIEW OF SERVICE REQUIREMENTS AND SUGGESTIONS

It is MAP policy that all exhaust, brake, steering, suspension, wheel alignment, drive-line, engine performance and maintenance, and heating, ventilation and air conditioning, and electrical services be offered and performed under the standards and procedures specified in these sections.

Before any service is performed on a vehicle, an inspection of the appropriate system must be performed. The results of this inspection must be explained to the customer and documented on an inspection form. The condition of the vehicle and its components will indicate what services/part replacements may be "Required" or "Suggested". In addition, suggestions may be made to satisfy the requests expressed by the customer.

When a component is suggested or required to be repaired or replaced, the decision to repair or replace must be made in the customers best interest, and at his or her choice given the options available.

This section lists the various parts and conditions that indicate a required or suggested service or part replacement. Although this list is extensive, it is not fully inclusive. In addition to this list, a technician may make a suggestion. However, any suggestions must be based on substantial and informed experience, or the vehicle manufacturers recommended service interval and must be documented.

Some conditions indicate that service or part replacement is

required because the part in question is no longer providing the function for which it is intended, does not meet a vehicle manufacturers design specification or is missing.

Example:

An exhaust pipe has corroded severely and has a hole in it through which exhaust gases are leaking. Replacement of the exhaust pipe in this case is required due to functional failure.

Example:

A brake rotor has been worn to the point where it measures less than the vehicle manufacturers discard specifications. Replacement of the rotor is required because it does not meet design specifications.

Some conditions indicate that a service or part replacement is suggested because the part is close to the end of its useful life or addresses a customers need, convenience or request. If a customers vehicle has one of these conditions, the procedure may be only to suggest service.

Example:

An exhaust pipe is rusted, corroded or weak, but no leaks are present. In this case, the exhaust pipe has not failed. However, there is evidence that the pipe may need replacement in the near future. Replacement of the pipe may be suggested for the customers convenience in avoiding a future problem.

Example:

The customer desires improved ride and/or handling,

but the vehicles shocks or struts have not failed. In this

case, replacement may be suggested to satisfy the customers

wishes. In this case, replacement of the shocks or struts may

not be sold as a requirement.

A customer, of course, has the choice of whether or not a shop will service his or her vehicle. He or she may decide not to follow some of your suggestions. When a repair is required, a MAP shop must refuse partial service on that system if, in the judgment of the service provider, proceeding with the work could create or continue an unsafe condition. When a procedure states that required or suggested repair or replacement is recommended, the customer must be informed of the generally acceptable repair/replacement options whether or not performed by the shop.

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.

The following reasons may be used for required and suggested services. These codes are shown in the "Code" column of the MAP Uniform Inspection & Communications Standards that follow:

Reasons to Require Repair or Replacement

A - Part no longer performs intended purpose

В - Part does not meet a design specification (regardless of

performance) С - Part is missing

NOTE: When a repair is required, the shop must refuse partial service to the system in question, if the repair creates or continues an unsafe condition.

Reasons to Suggest Repair or Replacement

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 vehicles

Original Equipment Manufacturer (OEM)

4 - Technicians 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

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

Condition Code Procedure

Bracket broken A .. Require repair or replacement.

Pipe bent out of

position B .. Require repair or replacement.

Pipe broken A .. Require repair or replacement.

Pipe cracked B .. Require repair or replacement.

Pipe leaking A Require replacement.

Pipe missing C Require replacement.

Pipe plugged A Require replacement.

Pipe weak due to corrosion, but no leaks

present 1 Suggest replacement.

Weld broken A .. Require repair or replacement.

EXHAUST CONNECTIONS

EXHAUST CONNECTION INSPECTION

Condition Code Procedure

Attaching hardware

incorrect B Require replacement of

hardware.

Clamp broken A Require replacement.

Clamp loose A . Require repair or replacement.

Clamp missing C Require replacement.

Corroded, affecting

structural integrity ... 1 Suggest replacement.

Incorrect type (i.e.

flange, ball & socket

etc.) B Require replacement.

Leaking A Require repair.

Loose A Require repair.

HANGERS

HANGER INSPECTION

Condition Code Procedure

Broken A Require replacement.

Corroded, affecting

structural integrity ... 1 Suggest replacement.

Incorrect type B Require replacement.

Loose A . . Require repair or replacement.

Missing C Require replacement.

Out of position B .. Require repair or replacement.

Rubber deteriorated 1 Suggest replacement.

HEAT RISERS (MECHANICAL EFE DEVICES)

HEAT RISER (MECHANICAL EFE DEVICE) INSPECTION

Condition Code Procedure

Broken A Require replacement of

affected parts.

Diaphragm inoperative ... A (1) Require replacement.

Leaking A . . Require repair or replacement.

Noisy 2 ... Suggest repair or replacement

of affected parts.

Seized A ... Require repair or replacement

of affected parts.

Spring broken B Require replacement of

spring(s).

Spring inoperative A Require replacement of

spring(s).

(1) - If the inoperative diaphragm is separate from the heat riser, then require replacement of the inoperative diaphragm. If the inoperative diaphragm is part of the heat riser, then replace the heat riser.

HEAT SHIELDS

HEAT SHIELD INSPECTION

Condition Code Procedure

Bent B . . Require repair or replacement.

Broken A Require replacement.

Corroded, affecting

structural integrity ... 1 Suggest replacement.

Loose A . . Require repair or replacement.

Missing C Require replacement.

MANIFOLDS (CAST AND TUBE TYPE)

MANIFOLD (CAST AND TUBE TYPE) INSPECTION

Condition Code Procedure

Air injection tube in

manifold broken A ... Require repair or replacement

of injection tube or replacement of manifold. Air injection tube in manifold corroded, affecting structural

integrity 1 Suggest replacement of

injection tube or manifold. Air injection tube in

manifold leaking A ... Require repair or replacement

of injection tube or replacement of manifold. Air injection tube in

manifold loose A Require repair.

Air injection tube in

manifold restricted .... A Require replacement of

injection tube or manifold. Air injection tube in manifold threads

damaged A Require repair of injection

tube or manifold. Air injection tube in manifold threads stripped

(threads missing) A Require replacement of

injection tube or manifold.
Bolt broken A ... Require replacement of bolts.

Bolt loose A Require tightening or

replacement of bolts.

Bolt missing C ... Require replacement of bolts.

Corroded, affecting

sealability A .. Require repair or replacement.

Cylinder head threads

stripped A ... Require repair or replacement

of cylinder head.

Gasket leaking A Require tightening or

replacement of gasket.

Heat stove bent B (1) Require repair or

replacement of stove.

Heat stove broken A (1) Require replacement

of stove.

Heat stove corroded, affecting structural

integrity 1 (1) Suggest replacement

of stove.

Heat stove missing C (1) Require replacement

of stove.

Manifold broken A . . Require repair or replacement.

Manifold cracked B . . Require repair or replacement.

Manifold warped A . . Require repair or replacement.

Out of specification .... B .. Require repair or replacement.

Stud broken A .... Require replacement of stud.

Stud missing C .... Require replacement of stud.

Stud threads damaged .... A ... Require repair or replacement

of stud.

Stud threads stripped
(threads missing) A .... Require replacement of stud.

(1) - Stove may not be available separately; this may require replacement of manifold.

MECHANICAL EFE DEVICES

See HEAT RISERS (MECHANICAL EFE DEVICES).

MUFFLERS AND RESONATORS

MUFFLER AND RESONATOR INSPECTION

Condition Code Procedure

Body shell distorted,

affecting performance or

structural integrity ... A Require replacement.

Corrosion hole A Require replacement.

Missing C Require replacement.

Mounting bracket broken . A . . Require repair or replacement. Mounting bracket

cracked B . . Require repair or replacement.

Nipple cracked A .. Require repair or replacement.

Nipple loose B Require replacement.

Outer wrap peeling

(exhaust not leaking) .. 1 Suggest replacement.

Plugged A Require replacement.

Puncture (other than a

drain hole) A Require replacement.

Rattling or knocking noise

from inside muffler .... B Require replacement.

Seam open (exhaust

leaking) A Require replacement.

Sound quality

unsatisfactory 2 .. Suggest replacement to address

customer need and/or request.

Split (exhaust leaking) . A Require replacement.

Weak due to corrosion, but

no leaks present 1 Suggest replacement.