Front Exhaust Pipe With Catalytic Converters And Front Muffler

Removing 

-- Remove the engine cover -arrows-.

Fig 1: Removing Engine Cover

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-- Remove the bolts -arrows- and air guide.

Fig 2: Identifying Bolts -Arrows- And Air Guide

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-- Remove both the lower air guide and the air guide hose.

-- Disconnect the connector -1- from the Mass Airflow (MAF) sensor -G70-.

Fig 3: Air Flow Housing, Electrical Connector And Guide Hose

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-- Remove the air guide hose -2-.

-- Remove the bolt -4- and the air filter housing.

-- Remove the air guide pipe bolt -arrow-.

Fig 4: Locating Air Guide Pipe Bolt

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-- Remove the air guide pipe; to do this, loosen the hose clamp -1-.

-- Press the release buttons and remove the air guide hose -2-.

-- Disconnect the electrical wire connector -arrow- for the Heated Oxygen Sensor (HO2S) -G39- and Oxygen Sensor (O2S) heater -Z19- and free up the wire.

Fig 5: Disconnecting Heated Oxygen Sensor (HO2S) G39 Harness Connector

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-- Remove the accessible nuts -arrows- for the front exhaust pipe/turbocharger from above.

Fig 6: Front Exhaust Pipe/Turbocharger Nuts

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AWD: 

Fig 7: Driveshaft Flexible Disc

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-- Mark position of flexible disc to bevel box flange for reinstallation.

-- Remove the driveshaft flexible disc bolts -arrows- from the bevel box while counter holding at the triangular flange with a lever.

Fig 8: Identifying Driveshaft Flange Shaft Seal

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All Vehicles: 

Fig 9: Electrical Connector For The Oxygen Sensor (O2S) After Three Way Catalytic Converter (TWC) -G130- And Heater For Oxygen Sensor (O2S) 1 After Catalytic Converter -Z29- (Under Cover)

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-- Remove the nuts -1 and 2- on the bracket for the oxygen sensor electrical connector under the underbody. Remove the cover.

-- Remove the bolt -3- and free up the electrical wire to the oxygen sensor.

-- Remove the connector coupling -arrow- from the bracket.

Fig 10: Electrical Connector -arrow-

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-- Disconnect the electrical connector to the Oxygen Sensor (O2S) after Three Way Catalytic Converter (TWC) -G130-.

-- Remove the remaining nuts -arrows- for the front exhaust pipe/turbocharger from below.

Fig 11: Front Exhaust Pipe/Turbocharger Nuts

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-- Remove exhaust system bracket and cross brace -arrows-.

Fig 12: Identifying Crossbrace Bolts -Arrows-

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-- Disconnect the exhaust system at the clamping sleeve -arrows-.

Fig 13: Clamping Sleeve -Arrows-

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-- Remove the front exhaust pipe with the catalytic converter and front muffler.

Installing 

Installation is carried out in the reverse order while noting the following:

• For the correct tightening specifications, refer to MUFFLER OVERVIEW .

-- Install driveshaft Removal and Installation .

-- Install exhaust system free of stress, refer to EXHAUST SYSTEM, ALIGNING .

Edition 6 29 2011