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Engine Exhaust System Chevrolet Malibu VI

Exhaust 2 illustrations ~2455 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Exhaust Crossover Pipe Bolt-3.5L25 N.m18 lb ft
Exhaust Crossover Pipe Heat Shield Bolt-3.5L10 N.m89 lb in
Exhaust Manifold Heat Shield Bolt-2.2L25 N.m18 lb ft
Exhaust Manifold Heat Shield Bolt-3.5L18 N.m12 lb ft
Exhaust Manifold Nut-2.2L12 N.m9 lb ft
Exhaust Manifold Nut-3.5L16 N.m12 lb ft
Exhaust Manifold Pipe to Exhaust Manifold Nut45 N.m33 lb ft
Exhaust Muffler Inlet Pipe Clamp Nut50 N.m37 lb ft
Flex Decoupler to Exhaust Manifold Nut-2.2L35 N.m26 lb ft
Intermediate Pipe to 3-Way Catalytic Converter Bolt34 N.m25 lb ft

Fastener Tightening Specifications

Diagnostic Starting Point - Engine Exhaust

Begin the system diagnosis by reviewing the system Description and Operation. Reviewing the information will help you determine the correct symptom diagnostic procedure when a malfunction exists. It will also help you determine if the condition described by the customer is normal operation. Refer to Symptoms - Engine Exhaust in order to identify the correct procedure for diagnosing the system.

Symptoms - Engine Exhaust

  1. Review the Exhaust System Description and Operation in order to familiarize yourself with the system functions. Refer to «Exhaust System Description»(/chevrolet/malibu/vi-2003-2006/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 explaination, refer to «Strategy Based Diagnosis»(/chevrolet/malibu/vi-2003-2006/remont/hoistjack/#general-information__strategy-based-diagnosis) in General Information.

Visual/Physical Inspection

  1. Inspect for aftermarket or non-OEM devices such as, but not including; tailpipe extensions, mufflers, and exhaust hangers. This 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»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  2. Poor acceleration Refer to «Restricted Exhaust»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  3. Poor fuel economy Refer to «Restricted Exhaust»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  4. Exhaust hissing noise Refer to «Exhaust Leakage»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system__exhaust-leakage) .
  5. Exhaust popping noise Refer to «Exhaust Leakage»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system__exhaust-leakage) .
  6. Exhaust rattle noise Refer to «Exhaust Noise»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system__exhaust-noise) .
  7. Loud exhaust noise Refer to «Exhaust Noise»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system__exhaust-noise) .
  8. Exhaust buzz, groan, humm noise Refer to «Exhaust Noise»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system__exhaust-noise) .

Test Description

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

  1. 3: 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 Gage. See «Special Tools and Equipment»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) . Removing the heated oxygen sensor (HO2S) may set a DTC. When finishing this diagnostic table, be sure to clear all codes.
  2. 4: This step will isolate the catalytic converter from the remainder of the exhaust system.
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
3CAUTION: Refer to Hot Exhaust System Caution in Cautions and Notices. Remove the pre-catalyst heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 in Engine Controls - 3.5L or Heated Oxygen Sensor (HO2S) Replacement (Pre-Catalyst) or Heated Oxygen Sensor (HO2S) Replacement (Post-Catalyst) in Engine Controls - 2.2L. Install the J 35314-A Exhaust Back Pressure Gage in place of the HO2S sensor. See Special Tools and Equipment . Start and run the vehicle. Increase and monitor the engine speed at 2,500 RPM. Observe the exhaust system back pressure reading on the gage. Does the reading exceed the specified value?9 kPa (1.25 psi)Go to Step 4Go to Step 7
4Turn the engine OFF and place the ignition in the lock position. Remove the J 35314-A . See Special Tools and Equipment . Install the pre-catalyst HO2S sensor. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 in Engine Controls - 3.5L or Heated Oxygen Sensor (HO2S) Replacement (Pre-Catalyst) or Heated Oxygen Sensor (HO2S) Replacement (Post-Catalyst) in Engine Controls - 2.2L. Remove the post-catalyst HO2S sensor. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 2 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 2 in Engine Controls - 3.5L or Heated Oxygen Sensor (HO2S) Replacement (Pre-Catalyst) or Heated Oxygen Sensor (HO2S) Replacement (Post-Catalyst) in Engine Controls - 2.2L. Install the J 35314-A in place of the post HO2S sensor. See Special Tools and Equipment . Start the engine. Increase and monitor the engine speed at 2,500 RPM. Observe the exhaust system back pressure reading on the gage. Does the reading exceed the specified value?9 kPa (1.25 psi)Go to Step 5Go to Step 6
5Inspect 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 7
6Replace the catalytic converter. Refer to Catalytic Converter Replacement (Bank 1) or Catalytic Converter Replacement (Bank 2) . Did you find and correct the condition?Go to Step 7
7Remove the J 35314-A . See Special Tools and Equipment . Install the post-catalyst HO2S sensor. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 2 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 2 in Engine Controls - 3.5L or Heated Oxygen Sensor (HO2S) Replacement (Pre-Catalyst) or Heated Oxygen Sensor (HO2S) Replacement (Post-Catalyst) in Engine Controls - 2.2L. Clear any codes. Road test the vehicle in order to verify the repair. Did you correct the condition?System OKGo to Step 2
CAUTION
Refer to Hot Exhaust System Caution in Cautions and Notices.

Restricted Exhaust

Exhaust Leakage

ProblemAction
CAUTION: 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 components to the specifications. Refer to Fastener Tightening Specifications .
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 Exhaust Manifold Replacement .
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. Refer to Muffler Replacement .
CAUTION
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
CAUTION: Refer to Hot Exhaust System Caution in Cautions and Notices. 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 muffle. Replace the faulty muffler. Refer to Muffler Replacement .
External rattle or vibration noiseInspect for a bent or loose hanger, loose heat shield, or loose clamp. Inspect for a 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. Replace the faulty catalytic converter, or muffler. Refer to one of the following procedures: Catalytic Converter Replacement (Bank 1) or Catalytic Converter Replacement (Bank 2) Muffler Replacement
CAUTION
Refer to Hot Exhaust System Caution in Cautions and Notices.

Exhaust Noise

Removal Procedure

  1. Raise the vehicle on a hoist. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/malibu/vi-2003-2006/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  2. Remove the exhaust manifold pipe-to-exhaust manifold nuts.
  3. Pull down on the exhaust manifold pipe just enough to free from the manifold studs and secure to the frame.
  4. Lower the vehicle.
  5. Remove the exhaust manifold heat shield bolts.
  6. Remove the heat shield.
  7. Disconnect the exhaust manifold heated oxygen sensor (HO2S) electrical connection.
  8. Remove the HO2S from the manifold.
  9. Remove the exhaust manifold nuts.
  10. Remove the exhaust manifold and discard the gasket.

Installation Procedure

  1. Install the new exhaust manifold gasket on the cylinder head.
  2. Install the exhaust manifold. Refer to «Exhaust Manifold Replacement»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  3. Install the exhaust manifold nuts. Tighten: Tighten the exhaust manifold-to-cylinder head nuts to 18 N.m (13 lb ft).
  4. Install the HO2S. Tighten: Tighten the oxygen sensor-to-exhaust manifold pipe to 45 N.m (33 lb ft).
  5. Connect the exhaust manifold HO2S electrical connection.
  6. Install the exhaust manifold heat shield. Tighten: Tighten the exhaust manifold heat shield bolts to 25 N.m (18 lb ft).
  7. Install the new exhaust manifold flange gasket onto the exhaust manifold flange studs.
  8. Raise the vehicle on a hoist. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/malibu/vi-2003-2006/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  9. Position the exhaust manifold pipe flange onto the exhaust manifold studs. Tighten: Tighten the exhaust manifold pipe-to-exhaust manifold nuts to 30 N.m (22 lb ft).
  10. Lower the vehicle.
  11. Start the vehicle and inspect for leaks.

Tools Required

J 39194-B Heated Oxygen Sensor Socket

  1. Remove the air intake tube. Refer to «Air Cleaner Intake Duct Replacement»(/chevrolet/malibu/vi-2003-2006/remont/testing-diagnostics/#engine-control-system-introduction-35l-lx9) in Engine Controls.
  2. Disconnect the front heated oxygen sensor (HO2S) from the connector at the side of the engine.
  3. Remove front HO2S using J 39194-B .
  4. Remove the exhaust manifold heat shield.
  5. Remove the upper exhaust manifold to cylinder head nuts.
  6. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/malibu/vi-2003-2006/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  7. Remove the crossover pipe. Refer to «Exhaust Crossover Pipe Replacement»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  8. Remove the front catalyst assembly. Refer to «Catalytic Converter Replacement (Bank 1)»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) or «Catalytic Converter Replacement (Bank 2)»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  9. Remove the exhaust manifold nuts.
  10. Remove the exhaust manifold assembly.
  11. Remove the exhaust manifold gasket.
  1. Install a new manifold gasket on the cylinder head.
  2. Install the exhaust manifold.
  3. Install the exhaust manifold nuts. Tighten: Tighten the exhaust manifold nuts to 16 N.m (12 lb ft).
  4. Install the front catalyst assembly and gasket. Refer to «Catalytic Converter Replacement (Bank 1)»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) or and «Catalytic Converter Replacement (Bank 2)»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  5. Install the crossover pipe and gaskets. Refer to «Exhaust Crossover Pipe Replacement»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  6. Install the exhaust manifold heat shield. Tighten: Tighten the exhaust manifold heat shield bolts to 18 N.m (12 lb ft).
  7. Install the HO2S into the exhaust manifold using J 39194-B . Tighten: Tighten the oxygen sensor-to-exhaust manifold pipe to 41 N.m (30 lb ft).
  8. Connect the HO2S electrical connector at the side of engine. Assure the connector is fully retained away from the exhaust manifold and heat shield edges.
  9. Install the air intake tube. Refer to «Air Cleaner Intake Duct Replacement»(/chevrolet/malibu/vi-2003-2006/remont/testing-diagnostics/#engine-control-system-introduction-35l-lx9) in Engine Controls.

J 39194-B Heated Oxygen Sensor Socket

  1. Remove the accessory drive belt. Refer to «Drive Belt Replacement»(/chevrolet/malibu/vi-2003-2006/remont/mechanical/#engine-mechanical-35l-lx9) in Engine Mechanical.
  2. Remove the generator. Refer to «Generator Replacement (L61)»(/chevrolet/malibu/vi-2003-2006/remont/charging-system/#battery-charging-system-and-starting-system) or «Generator Replacement (LX9)»(/chevrolet/malibu/vi-2003-2006/remont/charging-system/#battery-charging-system-and-starting-system__generator-replacement-lx9) in Engine Electrical.
  3. Disconnect the rear heated oxygen sensor (HO2S) connector.
  4. Remove the rear HO2S using J 39194-B .
  5. Remove the exhaust manifold heat shield.
  6. Remove the exhaust gas recirculation (EGR) pipe.
  7. Remove the upper exhaust manifold to cylinder head nuts.
  8. Remove the upward-pointing fastener from the rear catalyst assembly.
  9. Raise the vehicle.
  10. Remove the crossover pipe. Refer to «Exhaust Crossover Pipe Replacement»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  11. Remove the rear catalyst assembly. Refer to «Catalytic Converter Replacement (Bank 1)»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) or «Catalytic Converter Replacement (Bank 2)»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  12. Remove the exhaust manifold nuts.
  13. Remove the exhaust manifold assembly.
  14. Remove the exhaust manifold gasket.
  1. Install a new manifold gasket on the cylinder head.
  2. Install the exhaust manifold.
  3. Install the exhaust manifold nuts. Tighten: Tighten the exhaust manifold nuts to 16 N.m (12 lb ft).
  4. Install the rear catalyst assembly and gasket. Refer to «Catalytic Converter Replacement (Bank 1)»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) or «Catalytic Converter Replacement (Bank 2)»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  5. Install the crossover pipe and gaskets. Refer to «Exhaust Crossover Pipe Replacement»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  6. Install the EGR pipe. Tighten: Tighten the EGR pipe bolts to 25 N.m (18 lb ft).
  7. Install the exhaust manifold heat shield. Tighten: Tighten the exhaust manifold heat shield bolts to 18 N.m (12 lb ft).
  8. Install the HO2S into the exhaust manifold using J 39194-B . Tighten: Tighten the oxygen sensor-to-exhaust manifold pipe to 41 N.m (30 lb ft).
  9. Connect the HO2S electrical connector. Assure the connector and wiring are fully retained away from the exhaust manifold and heat shield edges.
  10. Install the generator. Refer to «Generator Replacement (L61)»(/chevrolet/malibu/vi-2003-2006/remont/charging-system/#battery-charging-system-and-starting-system) or «Generator Replacement (LX9)»(/chevrolet/malibu/vi-2003-2006/remont/charging-system/#battery-charging-system-and-starting-system__generator-replacement-lx9) in Engine Electrical.
  1. Remove the exhaust crossover pipe nuts.
  2. Remove the exhaust crossover pipe.
  3. If any of the studs on the exhaust system break, they can be replaced in a manner similar to a wheel lug.
  4. Using a hammer and drift, drive out the broken portion of the stud.
  5. Install a new stud by driving the replacement stud flange using a ball pein hammer.
  1. Using new gaskets, install the exhaust crossover pipe.
  2. Install the exhaust crossover pipe nuts. Tighten: Tighten the nuts to 25 N.m (18 lb ft).
  1. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/malibu/vi-2003-2006/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  2. Cut the intermediate pipe forward of the muffler using the service part as a template for making the cut (1).
  3. Remove the intermediate pipe bolts at catalytic converter downpipe.
  4. Remove the intermediate pipe from the hangers.
  5. Remove the intermediate pipe.
  6. Remove catalytic converter downpipe gasket.
  7. Clean the flange surface.
  1. Install catalytic converter downpipe gasket.
  2. Install the intermediate pipe to the hangers. Lubricate the exhaust system hangers with Dielectric Silicone Grease GM P/N 12345579 (Canadian P/N 1974984) to ease installation.
  3. Install the intermediate pipe bolts to catalytic converter. Tighten: Tighten the intermediate pipe bolts to 30 N.m (22 lb ft).
  4. Clamp the muffler (2) to the intermediate pipe (1).
  5. Align the two halves of the exhaust system to prevent contact with underbody components and torque the exhaust system clamp. Tighten: Tighten the exhaust clamp nuts to 50 N.m (37 lb ft).
  6. Lower the vehicle.

J 39194-B Heated Oxygen Sensor Wrench

  1. Remove the exhaust crossover pipe. Refer to «Exhaust Crossover Pipe Replacement»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  2. Remove HO2S 2 using the J 39194-B .
  3. Remove the 3 exhaust pipe nuts at the manifold.
  4. Remove the nuts at the outlet of the catalytic converter to crossover pipe.
  5. Inspect the exhaust pipe-to-exhaust manifold flange. Exhaust Pipe to Manifold Flange Warpage: Service Limit: 0.7 mm (0.028 in) max. Standard: 0.7 mm (0.028 in) max.
  1. Install a new gasket on the exhaust manifold studs.
  2. Install the front exhaust pipe-to-manifold nut and bolts. Tighten: Tighten the exhaust pipe-to-manifold nut and bolts to 31 N.m (23 lb ft).
  3. Install the catalytic converter outlet gasket and fasten the outlet to crossover pipe with the nuts. Tighten: Tighten the catalytic convertor to crossover pipe nuts to 31 N.m (23 lb ft).
  4. Install HO2S 2 using the J 39194-B . Tighten: Tighten the oxygen-sensor-to-exhaust manifold to 45 N.m (33 lb ft).
  5. Lower the vehicle to the ground, start the engine, and check for exhaust leaks.

J 39194-B Heated Oxygen Sensor Wrench

  1. Remove the exhaust crossover pipe. Refer to «Exhaust Crossover Pipe Replacement»(/chevrolet/malibu/vi-2003-2006/remont/exhaust/#engine-exhaust-system) .
  2. Remove HO2S 2 using the J 39194-B .
  3. Remove the 2 bolts and 1 exhaust pipe nut at the manifold.
  4. Remove the nuts at the outlet of the catalytic converter to crossover pipe.
  5. Inspect the exhaust pipe-to-exhaust manifold flange. Exhaust Pipe to Manifold Flange Warpage: Service Limit: 0.7 mm (0.028 in) max. Standard: 0.7 mm (0.028 in) max.
  1. Install a new gasket on the exhaust manifold studs.
  2. Install the rear exhaust pipe-to-manifold nut and bolts. Tighten: Tighten the exhaust pipe-to-manifold nut and bolts to 31 N.m (23 lb ft).
  3. Install the catalytic converter outlet gasket and fasten the outlet to crossover pipe with the nuts. Tighten: Tighten the catalytic convertor to crossover pipe nuts to 31 N.m (23 lb ft).
  4. Install the HO2S 2 using the J 39194-B . Tighten: Tighten the oxygen-sensor-to-exhaust manifold to 45 N.m (33 lb ft).
  5. Lower the vehicle to the ground, start the engine, and check for exhaust leaks.
IMPORTANTThe originally equipped, welded exhaust extension pipe can be cut and reused when installing a service muffler, if the extension pipe is in acceptable condition.
  1. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/malibu/vi-2003-2006/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  2. Support the exhaust muffler.
  3. Cut the exhaust extension pipe just forward of the weld at the front of the exhaust muffler.
  4. Release the muffler insulator from the underbody hanger and remove the exhaust muffler.
  5. Deburr the extension pipe end as necessary.
  1. Install the service muffler to the vehicle.
  2. Slide the muffler inlet pipe over the extension pipe, then install the muffler insulator to the underbody hanger.
  3. Install a service muffler clamp to the muffler inlet pipe. Position the clamp approximately 19 mm (3/4 in), from the edge of the muffler inlet, with the clamp nuts oriented away from the evaporative emission (EVAP) canister.
  4. Align the muffler and tailpipe to the vehicle underbody and rear bumper fascia.
  5. While maintaining muffler positioning, tighten the exhaust clamp nuts. Tighten: Tighten the nuts to 45 N.m (33 lb ft).
  6. Lower the vehicle.
  1. Raise and suitably support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/chevrolet/malibu/vi-2003-2006/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  2. Remove the muffler and resonator assembly from the intermediate or crossover pipe.
  3. Remove the muffler from the hangers.
  1. Install the muffler to the hangers.
  2. Install the muffler assembly to the intermediate pipe.
  3. Tighten the muffler assembly nuts. Tighten: Tighten the muffler assembly nuts to 20 N.m (15 lb ft).
  4. Lower the vehicle.

Exhaust System Description

IMPORTANTUse 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

Special Tools Illustration Tool Number/ Description J 35314-A Exhaust Back Pressure Gage J 39194-B Heated Oxygen Sensor Socket

Scheme 1

Scheme 1: Special Tools
Scheme 1: Special Tools

Scheme 2

Scheme 2
Scheme 2