Catalytic Converter, Removing And Installing, Catalytic Converter Without Particulate Filter: Removing

-- Remove the front muffler. Refer to FRONT MUFFLER, REMOVING AND INSTALLING, CATALYTIC CONVERTER WITHOUT PARTICULATE FILTER .

-- Release the retainer in direction of -arrow- and remove the vacuum hose -1-.

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Audi A4/A5: 

Fig 1: Coolant Expansion Tank.

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-- Left the clamp -left arrow-, remove the coolant hoses free them up and move it to the side.

Continuation for All Vehicles: 

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-- Remove the connector -2- for the Oxygen Sensor 1 After Catalytic Converter -GX7- -1- from the bracket and disconnect it (example photo).

-- Remove and disconnect the connector -2- for the Oxygen Sensor 1 Before Catalytic Converter -GX10- -1- from the bracket.

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-- Free up the wires for the heated oxygen sensors.

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-- Loosen the screw-type clamp -arrow- and remove the catalytic converter to the left side (example illustration).