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Engine Exhaust System Buick Encore I

Exhaust 8 illustrations ~1939 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Catalytic Converter Bracket Fastener (LUV)22 N.m16 lb ft
Catalytic Converter Flange to Exhaust Front Pipe Fastener (2HO)22 N.m16 lb ft
Catalytic Converter Heat Shield Fastener (2H0)8 N.m71 lb in
Catalytic Converter V-Clamp Fastener to Turbocharger (LUV)13 N.m115 lb in
Exhaust Front Pipe to Muffler Fastener17 N.m13 lb ft
Exhaust Front Pipe to Catalytic Converter22 N.m16 lb ft
Exhaust Front Pipe to Warm Up - 3 Way Catalytic Converter Fastener17 N.m13 lb ft
Exhaust Manifold Fastener (LUV)8 N.m71 lb in
Exhaust Manifold with Catalytic Converter to Cylinder Head Fasteners (2HO)20 N.m15 lb ft
Exhaust Manifold Heat Shield Fastener (LUV)8 N.m71 lb in
Exhaust Muffler Norma Clamp50 N.m37 lb ft

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»(/buick/encore/i-2012-2016/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»(/buick/encore/i-2012-2016/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»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system)
  2. Poor acceleration Refer to «Restricted Exhaust»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system)
  3. Poor fuel economy Refer to «Restricted Exhaust»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system)
  4. Excessive smoke diesel Refer to «Restricted Exhaust»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system)
  5. Exhaust hissing noise Refer to «Exhaust Leakage»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system__exhaust-leakage)
  6. Exhaust popping noise Refer to «Exhaust Leakage»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system__exhaust-leakage)
  7. Exhaust rattle noise Refer to «Exhaust Noise»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system__exhaust-noise)
  8. Loud exhaust noise Refer to «Exhaust Noise»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system__exhaust-noise)
  9. Exhaust buzz, groan, hum noise Refer to «Exhaust Noise»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system__exhaust-noise)

Diagnostic Aids

WARNINGRefer to Exhaust Service Warning .

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.
StepActionValue(s)YesNo
1Did you verify the customers complaint?Go to Step 2
2Did you review the exhaust symptoms diagnostic information and perform the necessary inspections?Go to Step 3Go to Symptoms - Engine Exhaust
3Is the system equipped with dual exhaust?Go to Diagnostic AidsGo to Step 4
4Remove the secondary air injection (AIR) check valve or the heated oxygen sensor (HO2S) that is in front of and closest to the catalytic converter. Refer to the affected component's service procedure. Install the J-35314-A Exhaust Back Pressure Gauge in place of the AIR check valve or HO2S sensor. Start the engine. Increase and monitor the engine speed at 2,000 RPM. Observe the exhaust system back pressure reading on the gauge. Does the reading exceed the specified value?14 kPa (2 psi)Go to Step 5Go to Step 8
5Turn the engine off and place the ignition in the lock position. Remove the J-35314-A Exhaust Back Pressure Gauge. Re-install the AIR check valve/HO2S sensor. Refer to the affected component's service procedure. Remove the post-catalyst HO2S sensor. Refer to the affected component's service procedure. Install the J-35314-A Exhaust Back Pressure Gauge in place of the post HO2S sensor. Start the engine. Increase and monitor the engine speed at 2,000 RPM. Observe the exhaust system back pressure reading on the gauge. Does the reading exceed the specified value?14 kPa (2 psi)Go to Step 6Go to Step 7
6Inspect the exhaust system for the following conditions: Damage in the exhaust pipe Debris in the exhaust pipe Muffler or resonator internal failure Two-layer exhaust pipe separation Did you find and correct the condition?Go to Step 8
7Replace the catalytic converter. Refer to the affected component's service procedure. Did you find and correct the condition?Go to Step 8
8Remove the J-35314-A Exhaust Back Pressure Gauge. Reinstall the AIR check valve or the post-catalyst HO2S sensor. Refer to the affected component's service procedure Clear any codes. Road test the vehicle in order to verify the repair. Did you correct the condition?System OKGo to Step 2

Restricted Exhaust

Exhaust Leakage

ProblemAction
WARNING: While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system. DEFINITION: An exhaust leak may show stains at the area of the leak. The leak may be felt by holding a hand close to the suspected areas or using a smoke pencil. The leak may make a popping or hissing noise.Refer to Symptoms - Engine Exhaust prior to beginning this table.
Misaligned or improperly installed exhaust system componentsAlign and tighten the exhaust system components to the specifications. Refer to Fastener Tightening Specifications . Ensure the exhaust hangers are in the proper locations and not loose.
Exhaust leaks at the following connections: Exhaust manifold to pipe Flanges Pipe clampsTighten the components to the specifications. Refer to Fastener Tightening Specifications .
Seals or gaskets leaking Exhaust manifold to cylinder head Exhaust pipes to exhaust manifold Catalytic converter connection EGR connections AIR connections to the exhaust manifold or cylinder headReplace the leaking seal or gasket. Refer to the affected components procedure for service.
Irregularities at the mating surfaces on the flange connectionsRepair as required or replace the affected component. Refer to the affected components procedure for service.
Exhaust manifold cracked or brokenReplace the exhaust manifold. Refer to the affected component's procedure for service.
Exhaust system component connection welds leakingReplace the leaking component. Refer to the affected component's procedure for service.
Muffler or resonator (if equipped) damaged or leaking at the seamsReplace the affected muffler or resonator. Refer to the affected component's procedure for service.
WARNING
While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system.

Exhaust Leakage

Exhaust Noise

ConditionAction
WARNING: While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system. DEFINITION: An audible or physical noise due to a faulty component or damaged components causing a loose or misaligned exhaust system resulting in a rattle or vibration noise, i.e. buzz, groan, hum.Refer to Symptoms - Engine Exhaust prior to beginning this table.
Popping or hissing noiseExhaust leak. Refer to Exhaust Leakage .
Loud exhaustCompare to a known good vehicle. Inspect for a damaged or failed muffler. Repair or replace the affected component. Refer to the affected component's service procedure.
External rattle or vibration noiseInspect for a bent or loose hanger, loose heat shield, or loose clamp. Inspect for an exhaust pipe causing interference. Repair or replace the affected component. Refer to the affected component's service procedure.
Internal rattleTest the components by tapping with a rubber mallet to confirm a rattle. Repair or replace the affected component. Refer to the affected component's service procedure.
WARNING
While engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system.

Exhaust Noise

Removal Procedure

  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Disconnect the heated oxygen sensor - position 2 from the exhaust front pipe.
  3. Remove the 2 fasteners (4) securing the warm up 3 way catalytic converter (3) to the exhaust front pipe (5).
  4. Discard the exhaust front pipe gasket (2).
  5. Remove the 3 fasteners (2) securing the exhaust front pipe (3) to the catalytic converter.
  6. Discard the exhaust front pipe gasket (1).
  7. Remove the exhaust front pipe (3).
  8. If you are replacing the exhaust front pipe, transfer the heated oxygen sensor.

Installation Procedure

  1. Install the exhaust front pipe (3) to the catalytic converter with a NEW gasket (1) and hand tighten the fasteners (2).
  2. Install the exhaust front pipe (5) to the warm up 3 way catalytic converter (3) with a NEW gasket (2) and tighten the fasteners (4) to 17 (13 lb ft).
  3. Tighten the exhaust front pipe fasteners (2) to 22 (16 lb ft).
  4. Connect the heated oxygen sensor - position 2 to the engine wiring harness.
  5. Start the engine and check for exhaust leaks.
WARNINGRefer to Exhaust Service Warning .
  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Disconnect the heated oxygen sensor - position 2 harness connector.
  3. Remove the 2 fasteners (3) securing the exhaust muffler (4) to the exhaust front pipe (1).
  4. Discard the exhaust front pipe gasket (2).
  5. Remove the 3 fasteners (1) securing the exhaust front pipe (3) to the catalytic converter.
  6. Discard the exhaust front pipe gasket (2).
  7. Remove the exhaust front pipe (3).
  8. If you are replacing the exhaust front pipe, transfer the heated oxygen sensor.
  1. Install the exhaust front pipe (3) to the catalytic converter with a NEW gasket (2) and hand tighten the fasteners (1).
  2. Install the exhaust front pipe (1) to the exhaust muffler (4) with a NEW gasket (2) and tighten the fasteners (3) to 17 (13 lb ft).
  3. Tighten the exhaust front pipe fasteners (1) to 22 (16 lb ft).
  4. Connect the heated oxygen sensor - position 2 to the engine wiring harness.
  5. Start the engine and check for exhaust leaks.

Scheme 1

Scheme 1: Catalytic Converter Replacement (2H0)
Scheme 1: Catalytic Converter Replacement (2H0)
CalloutComponent Name
WARNING: Refer to Exhaust Service Warning . WARNING: Refer to Protective Goggles and Glove Warning . Preliminary Procedure Remove the catalytic converter heat shield. Refer to Catalytic Converter Heat Shield Replacement (2H0) .
1Catalytic Converter to Exhaust Front Pipe Fastener (Qty: 3) CAUTION: Refer to Fastener Caution Tighten 22 N.m (16 lb ft)
2Exhaust Front Pipe
3Catalytic Converter to Exhaust front Pipe Gasket
4Exhaust Manifold Brace Fastener (Qty: 4) Tighten 20 N.m (15 lb ft)
5Catalytic Converter
6Exhaust Manifold Brace
7Heated Oxygen Sensor Tighten 42 N.m (31 lb ft)
8Catalytic Converter to Cylinder Head Fastener (Qty: 9) Tighten 20 N.m (15 lb ft)
9Catalytic Converter to Cylinder Head Gasket
WARNING
Refer to Exhaust Service Warning .
CAUTION
Refer to Fastener Caution

Catalytic Converter Replacement (2H0)

WARNINGRefer to Exhaust Service Warning .
  1. Remove the exhaust manifold heat shield. Refer to «Exhaust Manifold Heat Shield Replacement (LUV)»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system) .
  2. Remove the catalytic converter heated oxygen sensor - 1. Refer to «Heated Oxygen Sensor Replacement - Sensor 1»(/buick/encore/i-2012-2016/remont/testing-diagnostics/#engine-controls-and-fuel-14l-luj-luv-repair-instructions) .
  3. Remove the catalytic converter to the turbocharger clamp fastener and discard the clamp.
  4. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  5. Remove the exhaust front pipe fasteners (1) and discard the exhaust gasket (2).
  6. Remove the catalytic converter brace fasteners (1) from the catalytic converter brace (2).
  7. Remove the catalytic converter.
  1. Install the catalytic converter into the catalytic converter brace (2) and loosely tighten the fasteners (1).
  2. Install a NEW clamp into the position shown and loosely tighten the clamp fastener (1).
  3. Install the exhaust front pipe (3) to the catalytic converter with a NEW gasket (2) and tighten the fasteners (1) to 22 N.m (16 lb ft).
  4. Tighten the catalytic converter brace fasteners (1) to 22 N.m (16 lb ft).
  5. Lower the vehicle.
  6. Tighten the turbocharge clamp fastener to 13 N.m (115 lb in).
  7. Install the exhaust manifold heat shield. Refer to «Exhaust Manifold Heat Shield Replacement (LUV)»(/buick/encore/i-2012-2016/remont/exhaust/#engine-exhaust-system) .
  8. Install the catalytic converter heated oxygen sensor - 1. Refer to «Heated Oxygen Sensor Replacement - Sensor 1»(/buick/encore/i-2012-2016/remont/testing-diagnostics/#engine-controls-and-fuel-14l-luj-luv-repair-instructions) .
  9. Start the engine and check for exhaust leaks.
  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/encore/i-2012-2016/remont/ignition-switchsteering-lock/#general-information__lifting-and-jacking-the-vehicle) .
  2. Loosen the exhaust clamp fastener (4) and remove the exhaust muffler (2), from the warm up 3 way catalytic converter (1), and the exhaust isolator (3).
  3. Support the exhaust muffler (2) with mechanics wire.
  4. Remove the 2 fasteners (4) securing the warm up 3 way catalytic converter (3) to the exhaust front pipe (5).
  5. Remove the warm up 3 way catalytic converter (3) from the exhaust isolators (1) and remove the warm up 3 way catalytic converter from the vehicle.
  6. Discard the exhaust front pipe gasket (2).
  1. Install a NEW exhaust gasket (2) onto the exhaust front pipe (5).
  2. Install the warm up 3 way catalytic converter (3) into the exhaust isolators (1) and the onto the exhaust front pipe (5). Tighten the fasteners (4) to 17 (13 lb ft).
  3. Install the exhaust muffler (2) into the exhaust isolator (3) and the warm up 3 way catalytic converter (1). Tighten the exhaust clamp fastener (4) to 50 (37 lb ft).
  4. Lower the vehicle.
  5. Start the engine and check for exhaust leaks.

Scheme 2

Scheme 2: Exhaust Muffler Replacement (LUV)
Scheme 2: Exhaust Muffler Replacement (LUV)
CalloutComponent Name
WARNING: In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool. WARNING: Avoid contact with HOT components. Wear safety glasses and protective gloves to avoid personal injury. Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Exhaust Isolators NOTE: Clean and lubricate the exhaust isolator rods for ease of installation.
2Warm Up 3 Way Catalytic Converter
3Exhaust Muffler Clamp CAUTION: Refer to Fastener Caution . Tighten: 50 (37 lb ft)
4Exhaust Muffler Procedure With the aid of an assistant, lower the exhaust system from the vehicle.
WARNING
In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool.
WARNING
Avoid contact with HOT components. Wear safety glasses and protective gloves to avoid personal injury.
NOTE
Clean and lubricate the exhaust isolator rods for ease of installation.
CAUTION
Refer to Fastener Caution .

Exhaust Muffler Replacement (LUV)

Scheme 3

Scheme 3: Exhaust Muffler Replacement (2HO)
Scheme 3: Exhaust Muffler Replacement (2HO)
CalloutComponent Name
WARNING: In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool. WARNING: Avoid contact with HOT components. Wear safety glasses and protective gloves to avoid personal injury. Preliminary Procedure Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
1Exhaust Isolator (Qty: 5) NOTE: Clean and lubricate the exhaust isolator rods for ease of installation.
2Exhaust Gasket NOTE: Replace with a NEW gasket.
3Exhaust Muffler Fasteners (Qty: 2) CAUTION: Refer to Fastener Caution . Tighten 17 N.m (13 lb ft)
4Exhaust Muffler Procedure With the aid of an assistant, lower the exhaust system from the vehicle.
WARNING
In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool.
WARNING
Avoid contact with HOT components. Wear safety glasses and protective gloves to avoid personal injury.
NOTE
Clean and lubricate the exhaust isolator rods for ease of installation.
NOTE
Replace with a NEW gasket.
CAUTION
Refer to Fastener Caution .

Exhaust Muffler Replacement (2HO)

WARNINGRefer to Exhaust Service Warning .
  1. Disconnect the battery negative cable. Refer to «Battery Negative Cable Disconnection and Connection»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .
  2. Disconnect the heated oxygen sensor wiring harness plug.
  3. Remove the oil level indicator tube. Refer to Oil Level Indicator Tube Replacement.
  4. Disconnect the air conditioning compressor hose from the air conditioning compressor assembly. Refer to «Air Conditioning Compressor Hose Replacement (2H0)»(/buick/encore/i-2012-2016/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  5. Disconnect the air conditioning condenser hose from the compressor assembly. Refer to «Air Conditioning Condenser Hose Replacement (2H0)»(/buick/encore/i-2012-2016/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  6. Remove the wiring harness bracket fastener (2) and the wiring harness bracket (1).
  7. Remove the 2 exhaust manifold heat shield fasteners (4).
  8. Remove the exhaust manifold heat shield (3).
  1. Install the exhaust manifold heat shield (3).
  2. Install the 2 exhaust manifold heat shield fasteners (4) and tighten to 8 N.m (71 lb in).
  3. Install the wiring harness bracket (1) and the wiring harness bracket fastener (2) and tighten to 15 N.m (11 lb ft).
  4. Install the oil level indicator tube. Refer to Oil Level Indicator Tube Replacement.
  5. Connect the air conditioning compressor hose to the air conditioning compressor assembly. Refer to «Air Conditioning Compressor Hose Replacement (2H0)»(/buick/encore/i-2012-2016/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  6. Connect the air conditioning condenser hose to the compressor assembly. Refer to «Air Conditioning Condenser Hose Replacement (2H0)»(/buick/encore/i-2012-2016/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  7. Connect the heated oxygen sensor wiring harness plug.
  8. Connect the battery negative cable. Refer to «Battery Negative Cable Disconnection and Connection»(/buick/encore/i-2012-2016/remont/body-electrical/#battery-charging-system-and-starting-system) .

Scheme 4

Scheme 4: Catalytic Converter Front Heat Shield Replacement
Scheme 4: Catalytic Converter Front Heat Shield Replacement
CalloutComponent Name
WARNING: Refer to Exhaust Service Warning . WARNING: Refer to Eye Protection Warning . Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the exhaust muffler. Refer to Exhaust Muffler Replacement (LUV) , Exhaust Muffler Replacement (2HO) .
1Catalytic Converter Front Heat Shield Fastener (Qty: 6) CAUTION: Refer to Fastener Caution . Tighten 3 (26 lb in)
2Catalytic Converter Front Heat Shield
WARNING
Refer to Exhaust Service Warning .
WARNING
Refer to Eye Protection Warning .
CAUTION
Refer to Fastener Caution .

Catalytic Converter Front Heat Shield Replacement

Scheme 5

Scheme 5: Exhaust Crossover Pipe Heat Shield Replacement
Scheme 5: Exhaust Crossover Pipe Heat Shield Replacement
CalloutComponent Name
WARNING: Refer to Exhaust Service Warning . WARNING: Refer to Eye Protection Warning . Preliminary Procedures Remove the exhaust muffler. Refer to Exhaust Muffler Replacement (LUV) , Exhaust Muffler Replacement (2HO) .
1Exhaust Crossover Pipe Heat Shield Fastener (Qty: 3) CAUTION: Refer to Fastener Caution . Tighten 3 (26 lb in)
2Exhaust Crossover Pipe Heat Shield
WARNING
Refer to Exhaust Service Warning .
WARNING
Refer to Eye Protection Warning .
CAUTION
Refer to Fastener Caution .

Exhaust Crossover Pipe Heat Shield Replacement

Scheme 6

Scheme 6: Exhaust Manifold Heat Shield Replacement (LUV)
Scheme 6: Exhaust Manifold Heat Shield Replacement (LUV)
CalloutComponent Name
WARNING: In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool.
1Exhaust Manifold Heat Shield Bolts (Qty: 3) CAUTION: Refer to Fastener Caution . Tighten 8 N.m (71 lb in)
2Exhaust Manifold Heat Shield
WARNING
In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool.
CAUTION
Refer to Fastener Caution .

Exhaust Manifold Heat Shield Replacement (LUV)

Scheme 7

Scheme 7: Exhaust Rear Muffler Heat Shield Replacement
Scheme 7: Exhaust Rear Muffler Heat Shield Replacement
CalloutComponent Name
WARNING: Refer to Exhaust Service Warning . WARNING: Refer to Eye Protection Warning . Preliminary Procedures Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Remove the exhaust muffler. Refer to Exhaust Muffler Replacement (LUV) , Exhaust Muffler Replacement (2HO) .
1Exhaust Rear Muffler Heat Shield Fastener (Qty: 4) CAUTION: Refer to Fastener Caution . Tighten 3 (26 lb in)
2Exhaust Rear Muffler Heat Shield
WARNING
Refer to Exhaust Service Warning .
WARNING
Refer to Eye Protection Warning .
CAUTION
Refer to Fastener Caution .

Exhaust Rear Muffler Heat Shield Replacement

Exhaust System Description

Note. Use of non-OEM parts may cause driveability concerns.

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 CH-6179 KM-6179 Heated Oxygen Sensor Remover/Installer CH-6614 MKM-6614 83 95 667 Chain-type Pipe Cutter

Scheme 8

Scheme 8: Special Tools
Scheme 8: Special Tools