Coolant Thermostat

Removing

-- Drain the coolant. Refer to COOLANT, DRAINING AND FILLING .

-- Remove the bolt -1- from below.

Fig 1: Air Guide Hose Bolts, Air Guide Pipe Hose Clamps & Electrical Harness Connector

Courtesy of AUDI OF AMERICA, LLC

NOTE:

Ignore items -2, 3 and 4 and the arrow-.

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

Fig 2: Air Guide And Bolts

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

-- Disconnect the electrical connectors -arrow- and free up the electrical wire.

Fig 3: Air Guide Hose Bolts, Air Guide Pipe Hose Clamps & Electrical Harness Connector

Courtesy of AUDI OF AMERICA, LLC

-- Loosen the hose clamp -2- from above.

-- Remove the bolt -4- and the air guide pipe.

NOTE:

Ignore -1 and 3-.

-- Free up the coolant hose -2- and electrical wiring harness -1-.

Fig 4: Electrical Wiring Harness, Coolant Hose And Bolt

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-- Remove the bolt -arrow- and remove the bracket.

-- Remove the bolt -2- on the bracket for the after-run coolant pump -V51-.

Fig 5: After-Run Coolant Pump V51 Bracket Bolt

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NOTE:

The after-run coolant pump stays in the installation position.

Ignore -1 and arrows-.

-- Remove the coolant hoses -1 and 2- and lay them aside.

Fig 6: Coolant Hoses

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-- Remove the bolts -1 through 9- and remove the oil separator.

Fig 7: Identifying Oil Separator Tightening Sequence

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-- Loosen the nut -2-, remove the bolt -1- and move the support for the intake manifold to the right.

Fig 8: Identifying Intake Manifold Support, Nut And Bolt

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-- Remove bolts -arrows- and remove connecting pieces.

Fig 9: Coolant Thermostat Housing Bolts

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-- Remove the coolant thermostat.

Installing

For the correct tightening specifications, refer to COOLANT PUMP AND THERMOSTAT OVERVIEW .

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

NOTE:

Replace the seals and the O-rings.

The hose supports, air guide pipes and hoses must be free of oil and grease before installing.

Secure all hose connections with hose clamps of the same type as those equipped by the factory.

To mount the charge hoses on their connectors securely, spray the bolts on the used clamps with rust remover before installing.

-- Clean O-ring sealing surface.

-- Coat the O-ring with coolant.

-- Install the thermostat -4- into the housing -5- for the coolant pump and move it slightly forward -arrow-.

Fig 10: Identifying Thermostat, Housing And Components

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-- Carefully mount the connector -3- ; while doing this, insert the centering pin -2- into the guide -1-.

-- Install the oil separator. Refer to OIL SEPARATOR .

-- Install the intake manifold support. Refer to Removal and Installation .

-- Install the after-run coolant pump. Refer to After-Run Coolant Pump -V51- .

-- Air guides, installing with connector. Refer to AIR GUIDE PIPES AND HOSES WITH CONNECTOR COUPLING

-- Fill the coolant system. Refer to COOLANT, DRAINING AND FILLING .