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Engine Exhaust System Chevrolet Aveo I

Exhaust 2 illustrations ~1376 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
Catalytic Converter-to-Exhaust Manifold Nuts50 N.m37 lb ft
Connecting Pipe-to-Catalytic Converter Nuts40 N.m30 lb ft
Exhaust Manifold Cover Bolts15 N.m11 lb ft
Front Muffler-to-Connecting Pipe Nuts30 N.m22 lb ft
Front Muffler-to-Rear Muffler Nuts30 N.m22 lb ft
Post-Converter Heated Oxygen Sensor41 N.m30 lb ft

Fastener Tightening Specifications

Scheme 1

Scheme 1: Engine Exhaust System Component Views
Scheme 1: Engine Exhaust System Component Views
CalloutComponent Name
1Exhaust Manifold Shield
2Exhaust Manifold
3Exhaust Front Pipe Gasket (Upper)
4Exhaust Pup Converter (1.4/1.5L SOHC and 1.4/1.6L DOHC)
5Exhaust Front Pipe Gasket (Lower)
6Muffler Gasket
7Exhaust Front Pipe (1.4/1.5L SOHC and 1.4/1.6L DOHC)
8Underbody Protective Shield (Front Muffler)
9Underbody Protective Shield (Rear Muffler)
10Exhaust Rear Muffler
11Muffler Gasket
12Exhaust Front Muffler
13Exhaust Front Pipe (1.2L SOHC)
14Pup Converter Gasket (Lower)
15Exhaust Pipe Converter (1.2L SOHC)
16Pup Converter Gasket (Upper)

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/aveo/i-2003-2008/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.

Visual/Physical Inspection

  1. Inspect for aftermarket or non-OEM devices such as, but not including; tailpipe extensions, headers, and exhaust cutouts. 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.

Intermittents

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

Symptom List

  1. Loss of power-Refer to «Restricted Exhaust»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system) .
  2. Poor acceleration-Refer to «Restricted Exhaust»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system) .
  3. Poor fuel economy-Refer to «Restricted Exhaust»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system) .
  4. Excessive smoke-diesel-Refer to «Restricted Exhaust»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system) .
  5. Exhaust hissing noise-Refer to «Exhaust Leakage»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system__exhaust-leakage) .
  6. Exhaust popping noise-Refer to «Exhaust Leakage»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system__exhaust-leakage) .
  7. Exhaust rattle noise-Refer to «Exhaust Noise»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system__exhaust-noise) .
  8. Loud Exhaust noise-Refer to «Exhaust Noise»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system__exhaust-noise) .
  9. Exhaust buzz, groan, hum noise-Refer to «Exhaust Noise»(/chevrolet/aveo/i-2003-2008/remont/exhaust/#engine-exhaust-system__exhaust-noise) .

Diagnostic Aids

CAUTIONWhile engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system.

Test Description

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

  1. 4: The exhaust system has very low backpressure under normal conditions. If the exhaust system is restricted, a significant increase in exhaust pressure is noticed on the J 35314. Note: Removing the O2S 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. 7: 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.
StepActionValuesYesNo
1Did you verify the customer's 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 O2S that is in front of and closest to the catalytic converter. Install the J 35314-A in place of the O2S sensor. See Special Tools . Start the engine. Observe the exhaust system backpressure reading on the gage. Does the reading exceed the specified value?14 kPa (2 psi)Go to Step 5Go to Step 7
5Inspect the exhaust system for the following conditions: Damage to 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 7Go to Step 6
6Replace the catalytic converter. Refer to Catalytic Converter Replacement . Is replacement complete?Go to Step 7
7Remove the J 35314-A and reinstall the O2S sensor. See Special Tools . 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
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 components.Align 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 connections Exhaust gas recirculation (EGR) connections, if equippedReplace 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.
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 (Front) or Muffler Replacement (Rear) .
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: 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. Replace the faulty muffler. Refer to Muffler Replacement (Front) or Muffler Replacement (Rear) .
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. Replace the faulty catalytic converter, or muffler. Refer to one of the following procedures: Catalytic Converter Replacement Muffler Replacement (Front) Muffler Replacement (Rear)
CAUTION
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. Remove the rear heated oxygen sensor.
  2. Remove the connecting pipe mounting bracket bolt.
  3. Remove the connecting pipe nuts and the gasket from the catalytic converter.
  4. Remove the nuts from the front muffler pipe to the connecting pipe.
  5. Clean the sealing surfaces on the front muffler pipe flange and the connecting pipe.
  6. Check the connecting pipe for holes, damage, open seams, or other deterioration which could permit exhaust fumes to seep into the passenger compartment.

Installation Procedure

  1. Install the catalytic converter and the connecting pipe and the gasket to the front muffler pipe flange. Use the nuts to secure the converter and the connecting pipe. Tighten: Tighten the front muffler to connecting pipe nuts to 30 N.m (22 lb ft).
  2. Using the nuts and the gasket secure the connecting pipe to the catalytic converter. Tighten: Tighten the connecting pipe to catalytic converter nuts to 40 N.m (30 lb ft).
  3. Install the rear heated oxygen sensor. Tighten: Tighten the rear heated oxygen sensor to 41 N.m (30 lb ft).
  1. Remove the exhaust manifold cover with the bolts.
  2. Remove the catalytic converter upper flange nut.
  3. Remove the connecting pipe mounting bracket bolt.
  4. Remove the catalytic converter lower flange nuts.
  5. Remove the catalytic converter and the gasket.
  1. Install the catalytic converter and the gasket.
  2. Install the catalytic converter lower flange nuts and the connecting pipe mounting bracket. Tighten: Tighten the connecting pipe to catalytic converter nuts to 40 N.m (30 lb ft). Tighten the connecting pipe mounting bracket bolt to 40 N.m (30 lb ft).
  3. Install the catalytic converter upper flange nuts. Tighten: Tighten the catalytic converter to exhaust manifold nuts to 50 N.m (37 lb ft).
  4. Install the exhaust manifold cover bolts. Tighten: Tighten the exhaust manifold cover bolts to 15 N.m (11 lb ft).
  1. Remove the nuts and the gasket from the front muffler pipe to the connecting pipe flange.
  2. Remove the nuts and the gasket from the rear muffler pipe flange.
  3. Disconnect the front muffler from the rubber hanger.
  4. Remove the front muffler.
  5. Check the exhaust pipe and the front muffler for holes, damage, open seams, or other deterioration which could permit exhaust fumes to seep into the passenger compartment or the trunk.
  1. Connect the front muffler to the rubber hanger.
  2. Attach the front muffler and the gasket to the rear muffler using the nuts. Secure the front muffler to the rubber hanger. Tighten: Tighten the front muffler-to-rear muffler nuts to 30 N.m (22 lb ft).
  3. Loosely secure the front muffler assembly to the connecting pipe flange.
  4. Secure the front muffler assembly to the connecting pipe flange with the nuts. Tighten: Tighten the front muffler-to-connecting pipe nuts to 30 N.m (22 lb ft).
  1. Remove the nuts and the gasket from the rear muffler pipe flange-to-front muffler pipe flange.
  2. Detach the rear muffler assembly from the rubber hangers on the tail pipe end.
  3. Remove the rear muffler assembly.
  4. Check the rear muffler and the pipe for holes, damage, open seams, and other deterioration which could permit exhaust fumes to seep into the passenger compartment or the trunk.
  1. Secure the rear muffler assembly to the rubber hangers on the tail pipe end.
  2. Secure the nuts and the gasket from the rear muffler pipe flange-to-front muffler pipe flange. Tighten: Tighten the front muffler-to-rear muffler nuts to 30 N.m (22 lb ft).

Exhaust System Description

CAUTIONEngine exhaust can kill. It contains the gas carbon monoxide (CO), which you cannot see or smell. It can cause unconsciousness and death. You might have exhaust coming in if: Your exhaust system sounds strange or different. Your vehicle gets rusty underneath. Your vehicle was damaged in a collision. Your vehicle was damaged when driving over high points on the road or over road debris. Repairs were not done correctly. Your vehicle or exhaust system had been modified improperly. If you ever suspect exhaust is coming into your vehicle: Drive it only with all the windows down to blow out any CO; and Have your vehicle fixed immediately.
CAUTIONWhile engine is operating, the exhaust system will become extremely hot. To prevent burns avoid contacting a hot exhaust system.

Note. If there is any mis-positioning, incorrect installation, or failure of components in the brake system pipes, hoses, or wheel cylinders, check for brake damage. The exhaust system components must have adequate clearance from the floor pan to avoid overheating of the floor pan, damage to the passenger compartment carpets and damage to items in the luggage compartments.

Muffler

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

If holes, open seams or any deterioration is discovered upon inspection of the front muffler and pipe assembly, the complete assembly should be replaced. The same procedure is applicable to the rear muffler assembly.

Catalytic Converters

Note. The catalytic converters require the use of unleaded fuel only. Using leaded fuel will damage the catalytic converters and other emission system components.

The catalytic converters are emission control devices added to the exhaust system to reduce pollutants from the exhaust pipes.

The 3-way catalyst has coatings which contain palladium, platinum and rhodium, which simultaneously lower the levels of HC, CO and NOx.

Special Tools

Special Tools Illustration Tool Number/ Description J 35314-A Exhaust Back Pressure Gage

Scheme 2

Scheme 2: Special Tools
Scheme 2: Special Tools