Engine Exhaust System Cadillac ATS I

Fastener Tightening Specifications

Fastener Tightening Specifications

Adhesives, Fluids, Lubricants, and Sealers

Adhesives, Fluids, Lubricants, and Sealers

Symptoms - Engine Exhaust

1. Review the exhaust system description in order to familiarize yourself with the exhaust system components and the intended function of the components. Refer to «Exhaust System Description»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system__exhaust-system-description) .
2. All diagnostics on a vehicle should follow a logical process. Strategy Based Diagnostics is a uniform approach for repairing all systems. The diagnostic flow is the place to start when repairs are necessary and may always be used in order to resolve a system problem. For a detailed explanation, refer to «Strategy Based Diagnosis»(/cadillac/ats/i-2012-2014/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) .

Visual/Physical Inspection

1. Inspect for aftermarket or non-OEM devices such as, but not limited to; tailpipe extensions, headers, and exhaust cutouts. Any aftermarket exhaust system devices could affect the operation and proper performance of the exhaust system.
2. Verify the exact operating conditions under which the concern exists. Note factors such as engine RPM, engine temperature, engine load, and frequency of concern.
3. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause any symptom.

Intermittent

Test the vehicle under the same conditions that the customer reported in order to verify the system is operating as designed.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

1. Loss of power Refer to «Restricted Exhaust»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system)
2. Poor acceleration Refer to «Restricted Exhaust»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system)
3. Poor fuel economy Refer to «Restricted Exhaust»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system)
4. Excessive smoke diesel Refer to «Restricted Exhaust»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system)
5. Exhaust hissing noise Refer to «Exhaust Leakage»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system__exhaust-leakage)
6. Exhaust popping noise Refer to «Exhaust Leakage»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system__exhaust-leakage)
7. Exhaust rattle noise Refer to «Exhaust Noise»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system__exhaust-noise)
8. Loud exhaust noise Refer to «Exhaust Noise»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system__exhaust-noise)
9. Exhaust buzz, groan, hum noise Refer to «Exhaust Noise»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system__exhaust-noise)

Diagnostic Aids

For dual exhaust systems a quick check of exhaust flow will help determine which side of the exhaust system is restricted. The side that has less exhaust flow is the side that will be suspect, and diagnosis should begin there.

Note. This will not apply if the dual exhaust is equipped with an "H" pipe or similar configuration in which the exhaust flow would be equalized.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. 4 The exhaust system has very low back pressure under normal conditions. If the exhaust system is restricted, a significant increase in the exhaust pressure is noticed on the J-35314-A Exhaust Back Pressure Gauge. Removing the AIR check valve or HO2S sensor may set a DTC. When finishing this diagnostic table, be sure to clear all codes.
2. 5 This step will isolate the catalytic converter from the remainder of the exhaust system.
3. 8 Confirming that the condition has been fixed is essential. If the symptom still exists and the vehicle has a dual exhaust system, proceed to Step 2 and repeat diagnostic procedure on the opposite exhaust pipe.

Restricted Exhaust

Exhaust Leakage

Exhaust Leakage

Exhaust Noise

Exhaust Noise

Removal Procedure

1. Remove the exhaust manifold heat shield. Refer to «Exhaust Manifold Heat Shield Replacement (LCV)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .
2. If replacing the exhaust manifold, remove the heated oxygen sensor - sensor 1. Refer to «Heated Oxygen Sensor Replacement - Sensor 1 (LCV)»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-20l-ltg-or-25l-lcv-repair-instructions) .
3. Remove the catalytic converter from the exhaust manifold. Refer to «Catalytic Converter Replacement (LCV)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .
4. Remove and discard the exhaust manifold fasteners (1).
5. Remove the exhaust manifold (3) and discard the exhaust manifold gasket (2).

Installation Procedure

1. Clean all mating surfaces.
2. Install the exhaust manifold (3) to the cylinder head with a NEW gasket (2).
3. Install NEW exhaust manifold fasteners (1) and hand tighten.
4. Tighten the exhaust manifold fasteners in 3 passes in the sequence shown to 20 (15 lb ft).
5. Install the catalytic converter to the exhaust manifold. Refer to «Catalytic Converter Replacement (LCV)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .
6. Install the heated oxygen sensor - sensor 1. Refer to «Heated Oxygen Sensor Replacement - Sensor 1 (LCV)»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-20l-ltg-or-25l-lcv-repair-instructions) .
7. Install the exhaust manifold heat shield. Refer to «Exhaust Manifold Heat Shield Replacement (LCV)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .

1. Remove the exhaust manifold heat shield. Refer to «Exhaust Manifold Heat Shield Replacement (LTG)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .
2. Remove the turbocharger. Refer to «Turbocharger Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-20l-ltg-or-25l-lcv-repair-instructions-on-vehicle) .
3. Remove the exhaust manifold brace. Refer to «Exhaust Manifold Brace Replacement (LTG)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .
4. Remove the exhaust manifold fasteners (1) and discard.
5. Remove the exhaust manifold (3) and discard the exhaust manifold gasket (2).

1. Clean all mating surfaces.
2. Install the exhaust manifold (3) to the cylinder head with a NEW gasket (2).
3. Install NEW fasteners (1) and hand tighten.
4. Tighten the exhaust manifold fasteners in 3 passes in the sequence shown to 20 (15 lb ft).
5. Install the exhaust manifold brace. Refer to «Exhaust Manifold Brace Replacement (LTG)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .
6. Install the turbocharger. Refer to «Turbocharger Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-20l-ltg-or-25l-lcv-repair-instructions-on-vehicle) .
7. Install the exhaust manifold heat shield. Refer to «Exhaust Manifold Heat Shield Replacement (LTG)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .

Scheme 1

Exhaust Manifold Brace Replacement (LTG)

1. Remove the intake manifold cover. Refer to «Intake Manifold Cover Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-36l-lfx-repair-instructions-on-vehicle) .
2. Remove the secondary air injection bypass valve bank 1. Refer to «Secondary Air Injection Bypass Valve Replacement - Bank 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
3. Disconnect the heated oxygen sensor - bank 1 sensor 1. Refer to «Heated Oxygen Sensor Replacement - Bank 1 Sensor 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
4. Disconnect the heated oxygen sensor - bank 1 sensor 2. Refer to «Heated Oxygen Sensor Replacement - Bank 1 Sensor 2»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
5. Remove the right catalytic converter fasteners (1) and remove the right catalytic converter from the cylinder head.
6. Discard the exhaust gasket (3).
7. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/ats/i-2012-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
8. Remove the catalytic converter brace bracket fasteners (1) and remove the catalytic converter brace bracket (2).
9. Remove the left catalytic converter fasteners (1) and remove the exhaust muffler (4) from the left catalytic converter (3).
10. Discard the exhaust gasket (2).
11. Remove the rear exhaust isolator bracket fasteners (1) and remove the exhaust muffler (3) with the exhaust isolators (2).
12. Disengage the exhaust muffler (1) from the exhaust isolators (2) by pulling the exhaust system forward.
13. Remove the floor panel cross bar fasteners (1) and remove the floor panel cross bar (2).
14. With the help of a second technician, lower the exhaust muffler system (1) to the floor.

1. With the help of a second technician, install the right catalytic converter (2) to the cylinder head with a NEW gasket (3) and loosely tighten the fasteners (1).
2. Install the rear exhaust muffler (1) into the exhaust isolators (2).
3. Install the exhaust muffler (4) to the left catalytic converter (3) with a NEW gasket (2). Tighten the fasteners (1) to 50 (37 lb ft).
4. Install the rear exhaust isolator brackets (2) to the frame and tighten the fasteners (1) to 40 (30 lb ft).
5. Tighten the right catalytic converter fasteners (1) to 46 (34 lb ft).
6. Install the catalytic converter brace bracket (2) and tighten the fasteners (1) to 22 (16 lb ft).
7. Install the floor panel cross bar (2) and tighten the fasteners (1) to 22 (16 lb ft).
8. Connect the heated oxygen sensor - bank 1 sensor 1. Refer to «Heated Oxygen Sensor Replacement - Bank 1 Sensor 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
9. Connect the heated oxygen sensor - bank 1 sensor 2. Refer to «Heated Oxygen Sensor Replacement - Bank 1 Sensor 2»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
10. Install the secondary air injection bypass valve bank 1. Refer to «Secondary Air Injection Bypass Valve Replacement - Bank 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
11. Install the intake manifold cover. Refer to «Intake Manifold Cover Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-36l-lfx-repair-instructions-on-vehicle) .

1. Remove the exhaust manifold heat shield. Refer to «Exhaust Manifold Heat Shield Replacement (LCV)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .
2. Remove the exhaust manifold fasteners (1).
3. Remove the exhaust support brace fastener (1) from the catalytic converter (2).
4. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/ats/i-2012-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
5. Disconnect the heated oxygen sensor harness connector.
6. Remove the exhaust muffler fasteners (2) and remove the exhaust muffler (1) from the catalytic converter (4).
7. Discard the exhaust gasket (3).
8. Remove the catalytic converter brace fasteners (1) from the catalytic converter brace (2).
9. Lower the catalytic converter (3) to the floor.
10. Discard the catalytic to manifold seal.
11. Transfer part as necessary.

1. Install a NEW catalytic to manifold seal.
2. With the aid of a second technician, install the catalytic converter (2) into the exhaust manifold with a NEW seal (3).
3. Loosely tighten the exhaust manifold fasteners (1).
4. Install the catalytic converter support brace to the engine block and tighten the fastener (1) to 22 (16 lb ft).
5. Install the catalytic converter (3) with the catalytic converter brace (2), to the engine block, and tighten the fasteners (1) to 22 (16 lb ft).
6. Tighten the exhaust manifold fasteners (1) to 50 (37 lb ft).
7. Connect the heated oxygen sensor harness connector.
8. Install the exhaust manifold heat shield. Refer to «Exhaust Manifold Heat Shield Replacement (LCV)»(/cadillac/ats/i-2012-2014/remont/exhaust/#engine-exhaust-system) .
9. Install the exhaust muffler (1) to the catalytic converter (4) with a NEW gasket (3) and tighten the fasteners (2) to 50 (37 lb ft).
10. Start the vehicle and check for exhaust leaks.

1. Remove the intake manifold cover. Refer to «Intake Manifold Cover Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-20l-ltg-or-25l-lcv-repair-instructions-on-vehicle) .
2. Remove the fuel pump insulator. Refer to «Fuel Pump Insulator Replacement (Inner)»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-20l-ltg-or-25l-lcv-repair-instructions) , «Fuel Pump Insulator Replacement (Outer)»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-20l-ltg-or-25l-lcv-repair-instructions) .
3. Disconnect the heated oxygen sensor - 1.
4. Remove the turbocharger heat shield. Refer to «Turbocharger Heat Shield Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-20l-ltg-or-25l-lcv-repair-instructions-on-vehicle) .
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/ats/i-2012-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
6. Disconnect the heated oxygen sensor - 2.
7. Remove the catalytic converter fasteners (1) and remove the exhaust muffler (3).
8. Discard the catalytic converter gasket (2).
9. Support the front exhaust muffler pipe (3) with mechanics wire.
10. Remove the catalytic converter support brace bracket fastener (1) that secures the catalytic converter to the brace bracket (2).
11. Remove the turbocharger fasteners (1) and discard the turbocharger seal (2).
12. Remove the catalytic support brace fastener (1) and lower the catalytic converter to the floor.
13. If replacing the catalytic converter, transfer parts as necessary.

1. Clean the catalytic converter mating surfaces.
2. Install the catalytic converter (3) to the turbocharger with a NEW seal (2).
3. Loosely tighten the turbocharger fasteners (1).
4. Install the catalytic converter support brace (2) to the engine block and tighten the fastener (1) to 22 (16 lb ft).
5. Tighten the turbocharger fasteners (1) to 50 (37 lb ft).
6. Connect the heated oxygen sensor - 1.
7. Install the fuel pump insulator. Refer to «Fuel Pump Insulator Replacement (Inner)»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-20l-ltg-or-25l-lcv-repair-instructions) , «Fuel Pump Insulator Replacement (Outer)»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-20l-ltg-or-25l-lcv-repair-instructions) .
8. Install the turbocharger heat shield. Refer to «Turbocharger Heat Shield Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-20l-ltg-or-25l-lcv-repair-instructions-on-vehicle) .
9. Install the intake manifold cover. Refer to «Intake Manifold Cover Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-20l-ltg-or-25l-lcv-repair-instructions-on-vehicle) .
10. Install the catalytic converter brace bracket (2) fastener (1) and tighten to 22 (16 lb ft).
11. Install the exhaust muffler (3) to the catalytic converter with a NEW gasket (2). Tighten the fasteners (1) to 50 (37 lb ft).
12. Connect the heated oxygen sensor - 2.
13. Start the engine and check for exhaust leaks.

1. Disconnect the heated oxygen sensor - Bank 2 - Sensor 1.
2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/ats/i-2012-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
3. Disconnect the heated oxygen sensor - Bank 2 - Sensor 2.
4. Remove the exhaust muffler fasteners (1) and remove the exhaust muffler (4) from the left catalytic converter (3).
5. Discard the exhaust muffler gasket (2).
6. Remove the catalytic converter brace bracket fasteners (1) and remove the catalytic converter brace bracket (2).
7. Remove the left catalytic converter fasteners (1) and remove the catalytic converter (3) from the engine compartment.
8. Discard the exhaust gasket (2).
9. If replacing the left catalytic converter, transfer the heated oxygen sensors. Refer to «Heated Oxygen Sensor Replacement - Bank 2 Sensor 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) , and «Heated Oxygen Sensor Replacement - Bank 2 Sensor 2»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .

1. Clean all mating surfaces.
2. Install the left catalytic converter (3) to the cylinder head with a NEW gasket (2) and loosely tighten the fasteners (1).
3. Install the catalytic converter brace bracket (2) and tighten the fasteners (1) to 22 (16 lb ft).
4. Connect the heated oxygen sensor - Bank 2 - Sensor 2.
5. Install the exhaust muffler (4) to the left catalytic converter (3) with a NEW gasket (2). Tighten the fasteners (1) to 50 (37 lb ft).
6. Lower the vehicle.
7. Tighten the catalytic converter fasteners (1) to 46 (34 lb ft).
8. Connect the heated oxygen sensor - Bank 2 - Sensor 1.
9. Start the engine and check for exhaust leaks.

1. Remove the intake manifold cover. Refer to «Intake Manifold Cover Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-36l-lfx-repair-instructions-on-vehicle) .
2. Remove the secondary air injection bypass valve-right side , if equipped. Refer to «Secondary Air Injection Bypass Valve Replacement - Bank 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
3. Disconnect the heated oxygen sensor - bank 1 sensor 1. Refer to «Heated Oxygen Sensor Replacement - Bank 1 Sensor 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
4. Disconnect the heated oxygen sensor - bank 1 sensor 2. Refer to «Heated Oxygen Sensor Replacement - Bank 1 Sensor 2»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
5. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/ats/i-2012-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
6. Using a metal cut off wheel, make a cut at the clamp welded bracket shown above (1).
7. Mark either side of the production clamp (1), for proper alignment of replacement clamp location and muffler alignment.
8. Loosen the exhaust clamp fastener (2).
9. Remove the left catalytic converter fasteners (1) and remove the exhaust muffler (4) from the left catalytic converter (3).
10. Discard the exhaust gasket (2).
11. Remove the exhaust muffler (1) from the right catalytic converter (3) and discard the production Torca clamp (2).
12. Remove the right catalytic converter fasteners (1) and remove the right catalytic converter (2) from the cylinder head.
13. Discard the exhaust gasket (3).
14. Remove the catalytic converter brace bracket fasteners (1) and remove the catalytic converter brace bracket (2).
15. Remove the right catalytic converter.
16. If replacing the catalytic converter, transfer the oxygen sensors to the NEW catalytic converter.

1. Install the right catalytic converter (2) to the cylinder head with a NEW gasket (3). Tighten the fasteners (1) to 46 (34 lb ft).
2. Install the heated oxygen sensor - bank 1 sensor 1. Refer to «Heated Oxygen Sensor Replacement - Bank 1 Sensor 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
3. Install the heated oxygen sensor - bank 1 sensor 2. Refer to «Heated Oxygen Sensor Replacement - Bank 1 Sensor 2»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
4. Install the secondary air injection bypass valve-right side. Refer to «Secondary Air Injection Bypass Valve Replacement - Bank 1»(/cadillac/ats/i-2012-2014/remont/testing-diagnostics/#engine-controlsfuel-36l-lfx-repair-instructions) .
5. Install the intake manifold cover. Refer to «Intake Manifold Cover Replacement»(/cadillac/ats/i-2012-2014/remont/mechanical/#engine-mechanical-36l-lfx-repair-instructions-on-vehicle) .
6. Install the catalytic converter brace bracket (2) and tighten the fasteners (1) to 22 (16 lb ft).
7. Install the NEW Torca clamp (2) onto the right catalytic converter (3) and insert the exhaust muffler (1) into the exhaust Torca clamp.
8. Install the exhaust muffler (4) to the left catalytic converter (3) with a NEW gasket (2). Tighten the fasteners (1) to 50 (37 lb ft).
9. Tighten the NEW Torca clamp fastener (2) to 50 (37 lb ft).
10. Start the engine and check for exhaust leaks.

Scheme 2

Exhaust Rear Muffler Rear Hanger Replacement

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/ats/i-2012-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
2. Remove the floor panel crossbar fasteners (1) and remove the floor panel crossbar (2).
3. Remove the catalytic converter fasteners (2) and detach the exhaust muffler (1) from the catalytic converter (4).
4. Discard the exhaust gasket (3).
5. Support the front muffler exhaust pipe with mechanics wire.
6. Remove the exhaust muffler (2) from the exhaust isolators (1).
7. With the aid of a second technician, remove the exhaust muffler (2) from the exhaust isolator (1).
8. Lower the exhaust muffler (1) to the floor.

1. With the help of a second technician, install the exhaust muffler (2) into the exhaust isolators (1).
2. Install the exhaust muffler (2) into the exhaust isolator (1).
3. Install the exhaust muffler (1) to the catalytic converter (4) with a NEW gasket (3). Tighten the fasteners (2) to 50 (37 lb ft).
4. Install the floor panel crossbar (2) to the frame and tighten the fasteners (1) to 22 (16 lb ft).
5. Lower the vehicle.
6. Start the vehicle and check for exhaust leaks.

1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/cadillac/ats/i-2012-2014/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) .
2. Remove the catalytic converter fasteners (1) and remove the exhaust muffler (3).
3. Discard the catalytic converter gasket (2).
4. Support the front exhaust muffler pipe (3) with mechanics wire.
5. Remove the floor panel crossbar fasteners (1) and remove the floor panel crossbar (2).
6. Remove the exhaust muffler (2) from the exhaust isolators (1).
7. With the aid of a second technician, lower the exhaust muffler (1) to the floor.

1. Clean the exhaust muffler mating surfaces.
2. Install the exhaust muffler into the exhaust isolators (1).
3. Install the exhaust muffler (3) to the catalytic converter with a NEW gasket (2). Tighten the fasteners (1) to 50 (37 lb ft).
4. Install the floor panel crossbar (2) and tighten the fasteners (1) to 22 (16 lb ft).
5. Lower the vehicle.
6. Start the engine and check for exhaust leaks.

Scheme 3

Intermediate Body Exhaust Heat Shield Replacement

Scheme 4

Front Body Exhaust Heat Shield Replacement (Right)

Scheme 5

Front Body Exhaust Heat Shield Replacement (Left)

Scheme 6

Rear Body Exhaust Heat Shield Replacement

Scheme 7

Exhaust Manifold Heat Shield Replacement (LCV)

Scheme 8

Exhaust Manifold Heat Shield Replacement (LTG)

Exhaust System Description

The exhaust system carries exhaust gases, treated by the catalytic converter, through a resonator, if applicable and into the exhaust muffler where exhaust noise is lessened.

In order to secure the exhaust pipe to the exhaust manifold, a flange and seal-joint coupling is utilized. The exhaust system may utilize a slip-joint coupling design with a clamp and a U-bolt or a flange connection with a gasket.

Exhaust hangers and rubber insulators help to support the weight of the exhaust pipe along with insulating any exhaust system vibration, rattle, or noise.

Exhaust hangers also space the exhaust system away from the underbody of the vehicle and allows the exhaust system to expand as the exhaust system warms up.

Exhaust heat shields are used to protect the body and other components from damage due to the heat from the exhaust system.

The exhaust system may be comprised of the following components

1. Exhaust manifold
2. Exhaust pipes
3. Catalytic converters
4. Exhaust muffler
5. Exhaust resonator, if equipped
6. Exhaust tail pipe, if equipped
7. Exhaust hangers
8. Exhaust heat shields

Resonator

Some exhaust systems are equipped with a resonator. The resonator, located either before or after the muffler, allows the use of mufflers with less back pressure. Resonators are used when vehicle characteristics require specific exhaust tuning.

Catalytic Converter

The catalytic converter is an emission control device added to the engine exhaust system in order to reduce hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) pollutants from the exhaust gas.

The catalytic converter is comprised of a ceramic monolith substrate, supported in insulation and housed within a sheet metal shell. The substrate may be washcoated with 3 noble metals

1. Platium (Pt)
2. Palladium (Pd)
3. Rhodium (Rh)

The catalyst in the converter is not serviceable.

Muffler

The exhaust muffler reduces the noise levels of the engine exhaust by the use of tuning tubes. The tuning tubes create channels inside the exhaust muffler that lower the sound levels created by the combustion of the engine.

Special Tools

Illustration Tool Number/ Description EN 35314-A J 35314-A Exhaust Back Pressure Gauge J 35555 Vacuum Pump

Scheme 9

See also:
• Strategy Based Diagnosis
• Exhaust Service Warning
• Eye Protection Warning
• Heated Oxygen Sensor Replacement - Sensor 1 (LCV)
• Fastener Caution
• Turbocharger Replacement
• Hot Exhaust System Warning
• Intake Manifold Cover Replacement
• Secondary Air Injection Bypass Valve Replacement - Bank 1
• Lifting and Jacking the Vehicle
• Moving Parts and Hot Surfaces Warning
• Safety Glasses Warning
• Underbody Front Air Deflector Replacement - Right Side
• Exhaust System Description
• Restricted Exhaust
• Exhaust Leakage
• Exhaust Noise
• Symptoms - Engine Exhaust
• Fastener Tightening Specifications