Primary Catalytic Converter

Removing

-- On a vehicle with air suspension, activate vehicle lift mode. Refer to the appropriate service information .

-- Remove the noise insulation -1- and -2-. Refer to the appropriate service information .

Fig 1: Identifying Front/Rear Noise Insulation

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-- Drain the coolant. Refer to COOLING SYSTEM, DRAINING AND FILLING .

-- Remove the bolts -arrows- and the noise insulation bracket.

Fig 2: Identifying Bracket For Noise Insulation

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-- Remove the particulate filter. Refer to PARTICULATE FILTER .

-- Remove the heated oxygen sensor (HO2S) -G39-. Refer to Removal and Installation .

-- Remove the bolts -1- and -2- and then remove the heat shield from the turbocharger.

Fig 3: Identifying Bolts -1 To 2- And Turbocharger Heat Shield

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-- Remove the nuts -arrows-.

Fig 4: Identifying Nuts -Arrows-.

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-- Remove the sensor accessible from above:

Fig 5: Installation Location Inside Exhaust System Tract

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2 -

For catalyst temperature sensor 1 -G20- - only engines meeting Emissions Standard BIN 5

3 -

Exhaust gas temperature sensor 2 -G448- - only engines meeting Emissions Standard BIN 5

4 -

NOX sensor -G295-

-- Remove the exhaust gas temperature sensor 3 -G495- -1- accessible from underneath.

NOTE:

-5- was already removed.

-- Remove the bolt -1-.

Fig 6: Identifying Bolt -1-, Clamp -Arrow- And Left Rear Coolant Pipe

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-- Remove the left rear coolant pipe from the exhaust gas recirculation auxiliary cooler.

NOTE:

Ignore -arrow-.

-- Remove the heat shield -A- from the steering gear.

Fig 7: Identifying Universal Joint Bolt

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CAUTION:

Risk of distorting airbag spiral spring.

Separate universal joint from steering gear only when front wheels are in straight ahead position.
Secure steering wheel with adhesive tape to prevent position of steering wheel and steering gear from changing.

-- Remove the universal joint bolt -B-. Refer to Description and Operation .

-- Remove universal joint from steering gear.

-- Remove the bolt -arrow- on the preliminary catalytic converter strap.

Fig 8: Identifying Bolt -Arrow- From Exhaust Pipe

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WARNING:

The subframe could cause an accident if it is not secured.

Do not loosen the subframe bolts -1, 3 and 4-.

Fig 9: Identifying Bolts -4- And Engine Carrier Bolts -3-

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-- Remove the bolts -2- to be able to lower the rear subframe.

-- Remove the primary catalytic converter toward the rear.

Installing

Install in reverse order of removal. Note the following:

For the correct tightening specifications, refer to MUFFLER OVERVIEW .

NOTE:

Replace the seals and self-locking nuts.

During installation, all cable ties must be installed at the same location.

-- Install subframe. Refer to the appropriate service information .

-- Install universal joint on steering gear. Refer to Description and Operation .

-- Install the exhaust gas temperature sensor 3 -G495-. Refer to EXHAUST GAS TEMPERATURE SENSOR 3 .

-- Install the exhaust gas temperature sensor 2 -G448-. Refer to EXHAUST GAS TEMPERATURE SENSOR 2 .

-- Install the turbocharger heat shield TURBOCHARGER OVERVIEW .

-- Install the NOX sensor -G295- and the heated oxygen sensor (HO2S) -G39-. Refer to Removal and Installation .

-- Install the particulate filter PARTICULATE FILTER .

-- Install exhaust system free of stress. Refer to EXHAUST SYSTEM, INSTALLING .

-- Fill the coolant. Refer to COOLING SYSTEM, DRAINING AND FILLING => Filling .

-- Install the noise insulation bracket and the noise insulation. Refer to the appropriate service information .

-- On a vehicle with air suspension, deactivate vehicle lift mode. Refer to the appropriate service information .