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Emission Control Description & Operation - Diesel: Other Volkswagen Beetle A4

Engine Performance 7 illustrations ~915 words

Exhaust Gas Recirculation (EGR) System Components, Removing And Installing

1 - Intake manifold

2 - O-ring

  1. Always replace

3 - Intake manifold

  1. With EGR valve and regulator flap

4 - EGR Vacuum Regulator Solenoid Valve

  1. Component of intake manifold
  2. Can only be replaced as complete unit with intake manifold
  3. Check activation.

5 - 10 Nm

6 - From charge air cooler

7 - Gasket

  1. Always replace

8 - 25 Nm

9 - Exhaust manifold

10 - Connecting pipe

Scheme 44

Scheme 44
Scheme 44

Vacuum hose Connections, Diagram

1 - EGR Vacuum Regulator Solenoid Valve

2 - EGR Vacuum Regulator Solenoid Valve N18

3 - Non-return valve

4 - From brake booster

5 - Air filter housing

6 - Vacuum pump

Scheme 45

Scheme 45: Vacuum hose Connections, Diagram
Scheme 45: Vacuum hose Connections, Diagram

Exhaust Gas Recirculation System

Note. The function and control of the exhaust gas recirculation system is undertaken by the Diesel direct fuel injection (DFI) Engine Control Module (ECM) -J248- to the EGR vacuum regulator valve -N121-. Pulsed control makes every conceivable valve position possible. Replace self-locking nuts. Vacuum hose connection diagram. Refer to Vacuum hose connection diagram .

Vacuum Hose Connection Diagram

1 - Vacuum unit

  1. For exhaust gas recirculation change-over

2 - Intake Manifold Runner Control (IMRC) valve -N316

  1. For variable intake manifold

3 - Exhaust Gas Recirculation (EGR) cooler switch-over valve -N345

4 - Wastegate bypass regulator valve -N75

5 - Non-return valve

6 - Vacuum reservoir

7 - Vacuum unit

  1. With Turbocharger (TC) vane position sensor -G500-.
  2. For charge pressure control
  3. Integral part of turbocharger - cannot be replaced

8 - Vacuum unit

  1. For intake manifold runner control valve

9 - Vacuum connection

  1. Between tandem pump and brake servo

Scheme 46

Scheme 46
Scheme 46

Exhaust Gas Recirculation (EGR) System

Note. The Exhaust Gas Recirculation (EGR) system is activated by the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) -J248- via the Potentiometer for EGR -G212-. Exhaust Gas Recirculation (EGR), assembly overview --> See Exhaust Gas Recirculation (EGR), assembly overview .

Observe safety precautions --> See Safety precautions .

Note rules of cleanliness --> See Rules for cleanliness

Exhaust Gas Recirculation (EGR), assembly overview

  1. Vehicles with engine code BKW --> See «Exhaust Gas Recirculation (EGR) (vehicles with engine code BKW), assembly overview»(ref-338222-S00056739442009081800000)
  2. Vehicles with engine code BWF --> See «Exhaust Gas Recirculation (EGR) (vehicles with engine code BWF), assembly overview»(ref-338222-S10766168762009081800000)

Bypass flap with cooler for Exhaust Gas Recirculation (EGR) - Assembly overview (Vehicles with engine code BWF) --> See Bypass flap with cooler for Exhaust Gas Recirculation (EGR) (vehicles with engine code BWF), assembly overview

Connection diagram for vacuum hoses

  1. Vehicles with engine code BKW --> See «Vacuum hose connection diagram (vehicles with engine code BKW)»(ref-338222-S11359823652009081800000)
  2. Vehicles with engine code BWF --> See «Vacuum hose connection diagram (vehicles with engine codes BWF)»(ref-338222-S05393684182009081800000)

Exhaust Gas Recirculation (EGR) valve (vehicles with engine code BKW) , checking --> See Exhaust Gas Recirculation (EGR) valve (vehicles with engine code BKW), checking

Safety Precautions

CAUTIONWhen doing any repair work, especially in the engine compartment, pay attention to the following due to clearance issues: Route lines of all types (e.g. for fuel, hydraulic, additive, coolant and refrigerant, brake fluid, vacuum) and electrical wiring so that the original path is followed. To prevent damages to the lines, make sure there is sufficient clearance to all moving or hot components.

Rules For Cleanliness

When working on the exhaust gas recirculation (EGR) system, pay careful attention to the following "7 rules" of cleanliness

  1. Thoroughly clean all connections and the surrounding area before disconnecting.
  2. Place parts that have been removed on a clean surface and cover them. Do not use fluffy cloths!
  3. Carefully cover over opened components or seal, if repairs are not performed immediately.
  4. Only install clean components: Only unpack replacement parts immediately prior to installation. Do not use parts that have been stored loose (e.g. in tool boxes etc.).
  1. Supplied transport and protective packaging and sealing caps should only be removed immediately before installing.
  2. During repair, clean oil from connections and hose ends.
  3. When the system is open: Avoid working with compressed air if possible. Do not move vehicle unless absolutely necessary.

Vacuum Hose Connection Diagram (Vehicles With Engine Code BKW)

1 - EGR Vacuum Regulator Solenoid Valve N18 (electro-pneumatic)

  1. For cylinder bank 1

2 - EGR Vacuum Regulator Solenoid Valve (mechanical)

  1. For cylinder bank 1

3 - EGR Vacuum Regulator Solenoid Valve (mechanical)

  1. For cylinder bank 2

4 - EGR Valve 2 N213

  1. For cylinder bank 2

5 - Filter

6 - Vacuum line

  1. Between tandem pump and brake booster
  2. Check for secure seating

7 - Tandem pump

  1. Component location: Cylinder bank 1
  2. For fuel and vacuum supply
  3. Must not be disassembled

Scheme 47

Scheme 47
Scheme 47

Vacuum Hose Connection Diagram (Vehicles With Engine Codes BWF)

1 - Vacuum actuator

  1. For cylinder bank 1

2 - Vacuum actuator

  1. For cylinder bank 2

3 - Vacuum tube

4 - Exhaust Gas Recirculation (EGR) Cooler Switch-Over Valve N345

  1. For cylinder bank 1
  2. Component location: at right rear wheelhousing

5 - Exhaust Gas Recirculation (EGR) Cooler Switch-Over Valve 2 N381

  1. For cylinder bank 2
  2. Component location: at right front wheelhousing

6 - Tandem pump

  1. Component location: Cylinder bank 1
  2. For fuel and vacuum supply
  3. Must not be disassembled

7 - From brake booster

Scheme 48

Scheme 48
Scheme 48

Exhaust Gas Recirculation (EGR) Valve (Vehicles With Engine Code BKW), Checking

Special tools, testers and auxiliary items required

  1. Hand vacuum pump V.A.G 1390. (Scheme 49)

Work sequence

  1. Remove connecting hose charge air pipe/intake manifold.

Note. With connector couplings, follow the installation instructions closely.

  1. Disconnect vacuum hose at EGR vacuum regulator solenoid valve.
  2. Connect hand vacuum pump with additional equipment V.A.G 1390 to valve.
  1. Operate hand vacuum pump and observe diaphragm rod. Diaphragm rod must move in direction of - arrow -.
  2. Disconnect hose of hand vacuum pump from EGR valve. Diaphragm rod must move back in opposite direction of - arrow - into output position.

Scheme 49

Scheme 49
Scheme 49

Scheme 50

Scheme 50
Scheme 50

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