Overview - turbocharger, part 1

WARNING: This page is about a different car, the 2024 Audi A4 allroad. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Exploded View Of Turbocharger (Part 1)

Courtesy of AUDI OF AMERICA, LLC

O-Ring
- Replace after removing
Turbocharger Recirculation Valve -N249-
- Assembly is only possible in one position because of the offset holes
- Removing and Installing. Refer to Turbocharger Recirculating Valve -N249-, REMOVING AND INSTALLING .
Bolt
- 9 Nm
O-Ring
- Replace after removing
- Coat with coolant
Bolt
- 9 Nm
Coolant Return Line
Locking Spring
- Replace after removing
Ball Socket
Charge Air Pressure Control Module -GX34-
- Removing and Installing. Refer to Charge Air Pressure Control Module -GX34-, REMOVING AND INSTALLING .
Nut
- 8 Nm
Control Rod
Nut
- 8 Nm
Locking Spring
- Replace after removing
Ball Socket
Bolt
- 9 Nm
Locking Plate
- Quantity: 2
- Replace after removing
- Installing. Refer to Fig 4.
Nut
- Replace after removing
- Coat the threaded pins with hot bolt paste. Refer to the Parts Information.
- Tightening specification and sequence. Refer to Fig 3.
Seal
- Replace after removing
Threaded Pin
- Screw-in depth and tightening specification. Refer to Fig 2.
Turbocharger
- Removing and Installing. Refer to TURBOCHARGER, REMOVING AND INSTALLING .
O-Ring
- Replace after removing
- coat with engine oil
Oil Return Line
O-Ring
- Replace after removing
- coat with engine oil
Bolt/Double Bolt
- 25 Nm
Bolt
- 9 Nm

Check the screw-in depth of the threaded pin

Fig 2: Check the Screw-in Depth of the Threaded Pin

Courtesy of AUDI OF AMERICA, LLC

-- Tighten the threaded pin -1- to 23 Nm.

-- Measure the dimension -a- of the sealing surface of the cylinder head to the collar on the threaded pin.

At dimension -a- less than or equal to 2.4 mm: tightening specification 23 Nm OK
At dimension -a- more than 2.4 mm: tightening specification 27 Nm.

Turbocharger - tightening specification and sequence

Fig 3: Turbocharger - Tightening Sequence

Courtesy of AUDI OF AMERICA, LLC

Replace the nuts after removing.

-- Tighten the bolts in steps in the sequence shown:

Step	Nuts	Tightening Specifications
1.	-1 to 4-	Install all the way by hand
2.	-1 and 2-	10 Nm
3.	-3 and 4-	25 Nm
4.	-1 and 2-	25 Nm

Install the locking plates

Fig 4: Install the Locking Plates

Courtesy of AUDI OF AMERICA, LLC

Pay attention to distortion of the sprockets.

The locking plates are pressed onto the nuts using the following tools:

Pry bar
¹ /₂ "- EGR Temp. Sensor Socket - 14mm with extension
Hammer
Wrench - 14 mm

-- Press on the locking plates for easy accessible nuts using the ¹ /₂ "- EGR Temp. Sensor Socket - 14mm with extension and the hammer.

-- Press on the locking plates for difficult accessible nuts using the Wrench - 14 mm and the pry bar, at the same time support the pry bar on the turbocharger.