2.7.4.4 Rear Muffler Assembly

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2.7.4.5 Front Exhaust Insulation Panel

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2.7.4.6 Front Muffler Heat Shield

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2.7.5 Diagnostic Information and Procedures
2.7.5.1 Diagnostic Description

Refer to "Description and Operation" in the

2.7.2.1

 

Exhaust Manifold

Get familiar with the system functions and operation before start

system diagnostics, as this will help with the correct diagnostic steps, more importantly, it will also help to determine whether the
customer described situation is normal.

2.7.5.2 Visual Inspection

–

Check installed after market equipment that may affect the operation of the exhaust system.

–

Check the easy to access system components to identify whether there are significant blockages or leakage.

–

Check whether the color of the exhaust gas is normal.

2.7.5.3 Exhaust System Blockage

When the engine loses power, fuel economy becomes worse or acceleration performance is poor, check whether there is "exhaust
system blockage" fault, use the exhaust back-pressure to monitor whether the back-pressure is more than 50 kPa to confirm the
fault. The fault may be caused by following reasons:

–

Exhaust pipe is damaged.

–

There are debris in exhaust pipes.

–

Muffler or resonator internal faults.

–

Exhaust pipe internal corrosion blocks the rear exhaust port.

2.7.5.4 Exhaust System Leakage

If the engine has "hiss" or a burst sound sound when running, check whether there is "Exhaust System Leakage" fault, as shown in
the following table:

Exhaust system components misaligned or incorrectly installed

–

Position and tighten the exhaust system components to the
specified torque. Refer to "Engine Exhaust System" in
the

2.7.1.1

 

Fastener Tightening Specifications

.

–

Make sure that the exhaust pipe hook is in the right place and
is not loose.

Exhaust leak at the following connections:

–

Exhaust manifold and the three-way catalytic converter

–

Flange

Tighten the related components to the specified torque. Refer to
the "Engine Exhaust System" in the

2.7.1.1

 

Fastener Tightening

Specifications

.

 

 
Seal or Gasket Leak:
 

–

Exhaust Manifold and Cylinder Head Cover

–

Exhaust Manifold and The Three-Way Catalytic Converter

–

Three-Way Catalytic Converter and Front Muffler

–

Front Muffler and Rear Muffler

Replace the leaking seals or gasket.

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