Audi Workshop Service and Repair Manuals

Removing and installing turbocharger

t  Used oil collection and extraction unit -V.A.G 1782-

Removing   Note All cable ties which are released or cut open when removing must be fitted in the same position when installing. –  Take off engine cover panel -arrows-.   WARNING Hot steam or hot coolant can escape when expansion tank is opened; cover filler cap with cloth and open carefully. –  Open filler cap on coolant expansion tank

–  Remove noise insulation panels (centre and right) -arrows-. –  Drain off coolant → Chapter.

Vehicles with front-wheel drive: –  Unbolt heat shield for drive shaft (right-side). –  Remove drive shaft (right-side) → Rep. Gr.40. Vehicles with four-wheel drive: –  Remove bevel box → Rep. Gr.34.

All models: –  Unbolt protective cover -2--arrows-. –  Unplug electrical connectors and move aside wiring for Lambda probes -1- and -3-.   Note

To avoid any damage, the flexible joint in the front exhaust pipe must not be bent more than 10°. –  Unscrew nuts -arrows- securing front exhaust pipe to turbocharger.

–  Disconnect exhaust system at clamp -arrows- and push clamp towards rear of vehicle. –  Detach front exhaust pipe with catalytic converter. –  Place used oil collection and extraction unit -V.A.G 1782- under engine and drain engine oil.

–  Remove air intake hose -1- between top air pipe and bottom air pipe. –  Unbolt bracket -2- or retaining clip (depending on version) for top air pipe. –  Remove oil return pipe -3-.

–  Slacken bolted connection -3- for turbocharger bracket a few turns. –  Remove bolts -1- and -2- and detach bracket for turbocharger. –  Unbolt bracket for coolant return pipe -4-. –  Unbolt coolant supply pipe -5- at cylinder block.

–  Detach hoses -1- and -2- from turbocharger.

–  Detach air intake hose -1- leading to secondary air pump at air cleaner housing. –  Release hose clip -2- and detach air duct from air mass meter -G70-. –  Unplug electrical connector at air mass meter -G70- -item 3-. –  Unscrew bolts -4- and -5- and remove air cleaner housing.

–  Detach mechanical air recirculation valve -3-, pressure control valve for crankcase breather -6- and charge pressure control solenoid valve -N75--item 4- from air duct. –  Pull locking clip out at turbocharger connection and detach air duct -5-.   Note Seal off opening in turbocharger intake system with a clean cloth. –  Detach hoses -1- and -2- from top air pipe.

–  Detach coolant return hose -arrow- to turbocharger at Y-piece on right side next to cylinder head.

–  Disconnect air intake hose -3- leading to turbocharger from top air pipe. –  Unscrew bolts -2- and -5- on retaining clip for top air pipe. –  Unscrew bolts -1- and -4- for heat shield at back of cylinder head. –  Remove top air pipe and heat shield.

–  Unbolt turbocharger from exhaust manifold -arrows-. –  Remove gasket. The turbocharger will drop slightly.   Note Seal off opening in turbocharger intake system with a clean cloth.

–  Unscrew nuts -arrows- at exhaust manifold (accessible from above). –  Remove washers and exhaust manifold.

–  Unscrew retainer for oil supply pipe at turbocharger -arrow-. –  Re-connect bracket for turbocharger to cylinder block.

–  Disconnect oil supply pipe -2- and coolant return pipe -1- at turbocharger. –  Detach spacer sleeve below connection for coolant return pipe. –  Detach coolant return pipe. –  Unscrew bracket for turbocharger from cylinder block and detach turbocharger. Installing Installation is carried out in the reverse order; note the following:   Note t  Renew gaskets, seals and self-locking nuts. t  Fill turbocharger with engine oil at connection for oil supply pipe. t  Fit all heat insulation sleeves in the original position when installing. t  Hose connections and hoses for charge air system must be free of oil and grease before assembly. t  Secure all hose connections with the correct type of hose clips (same as original equipment) → Parts catalogue. t  Charge air system must be free of leaks. t  Fit all cable ties in the original positions when installing. –  Loosely attach turbocharger bracket to turbocharger. –  Fit turbocharger onto engine from underneath and attach bracket to cylinder block (hand-tight).

–  Screw on oil supply pipe -2- and retainer. –  Connect coolant return pipe -1- with spacer sleeve to turbocharger. –  Unscrew bracket for turbocharger from cylinder block again. –  Fit exhaust manifold. –  Bolt turbocharger to exhaust manifold. Vehicles with front-wheel drive: –  Install drive shaft (right-side) → Rep. Gr.40. Vehicles with four-wheel drive: –  Install bevel box → Rep. Gr.34. All models: –  Check oil level → Chapter. –  Fill cooling system → Anchor.   Note After installing turbocharger, allow engine to idle for approx. 1 minute and do not rev up immediately to ensure turbocharger is supplied with oil. Tightening torques

Component		Nm
Exhaust manifold to cylinder head		30 1)
Coolant supply pipe to:	Turbocharger	35
	Cylinder block	35
Coolant return pipe to turbocharger		35
Bracket for coolant return pipe to cylinder block		23
Oil supply pipe to turbocharger		30
Bracket for coolant supply pipe to turbocharger		10
Turbocharger to exhaust manifold		35 2)3)
Bracket for turbocharger to:	Cylinder block	25
	Turbocharger	45
Retainer for oil supply pipe to cylinder head		10
Heat shield to cylinder head		23
Oil return pipe to:	Sump	10
	Turbocharger	10
Front exhaust pipe with catalytic converter to turbocharger		40
Drive shaft heat shield to cylinder block		35
Hose clips for air hoses		3.5
l  1) Renew nuts. l  2) Renew bolts. l  3) Coat threads and contact surface of bolt heads with high-temperature paste; for high-temperature paste refer to → Parts catalogue.