Part 1
WM 100119 Removing and installing engine
Tools
Technical values
Preliminary work
Special equipment-specific features are described in the notes.
1. Position the vehicle at the take-up points provided on a lifting platform. => Lifting the vehicle
2. Fix steering wheel with wheels in straight-ahead position (engage steering column lock or clamp steering wheel in centre position with steering wheel holder)! If this is not done, the airbag contact unit will have to be put in centre position after installation of the steering gear! -> 945019 Removing and installing steering-column switch Service and Repair
3. Put on protection covers.
4. Read out the DME fault memory. Write down or print the result.
5. Move the Tiptronic selector lever to position N.
6. Disconnect the battery. -> 9000IN00 Work instructions after disconnecting the battery
7. Remove front wheels. -> 44051900 Removing and installing wheel - section on "Removing"
8. Remove the front wheel housing liners. -> 505619 Removing and installing front wheel housing liner - section on "Removing" Service and Repair
9. Remove engine guard with transverse strut. -> 108019 Removing and installing engine guard - section on "Removing" 108019 Removing and installing engine guard
10. Drain coolant. -> 193817 Draining and filling coolant (includes bleeding) Service and Repair
11. Remove engine compartment trim panels. -> 700219 Removing and installing front trim (engine compartment) - section on "Removing"
12. Move bonnet into service position -> 553119 Removing and installing front gas spring Service and Repair.
13. Remove cover of plenum panel. -> 664419 Removing and installing cowl panel cover - section on "Removing" Service and Repair
14. Evacuate the air conditioning system. -> 870317 Draining and filling refrigerant Service and Repair
15. Completely remove intake manifold between the air cleaner and throttle valve. -> 243519 Removing and installing air box for throttle housing (intake pipes upstream of throttle valve) Service and Repair
16. Remove right cross panel. -> 508119 Removing and installing cross panel - section on "Removing" Service and Repair
17. Remove air cleaner housing cover and filter element.
Information
- The air tube is only present in vehicles with air suspension.
17.1. Remove the air line on the air cleaner cover. To do this, unclip the green cap. Insert a screwdriver into the notch in the cap and lever the cap off.
Cap on air line
17.2. Push the circlip into the adapter -1- and then pull it off together with the adapter -2-.
Circlip
17.3. Clip the green cap on again after disassembly.
Cap
17.4. Remove air cleaner cover. Undo the fastening clamps on the air cleaner housing. Pull air cleaner cover up and out.
Fastening clamps on air cleaning housings
17.5. Remove air-cleaner element.
18. On vehicles with manual transmission, work on peripheral units must be performed as described in -> 343519 Removing and installing transmission - section on "Removing" Removal and Replacement.
Tools and materials
Tools
Tool setup - Master Gear unit elevating platform WE 1206 with suitable setup kit.
Lifting platform
Tool overview
Complete structure of the base carrier with mounting mandrels
Removing engine
WARNING
Highly inflammable or explosive materials
- Danger of fire or explosion
-> Avoid contact with hot parts or sources of ignition.
-> Use suction to remove ignitable vapors.
-> Attach warning sign in a clearly visible position.
WARNING
Caustic fluids
- Danger of chemical burns
-> Avoid contact with caustic fluid.
-> Wear personal protective gear.
-> Ensure that there is good ventilation.
-> If you do come into contact, wash off immediately with plenty of warm water and contact a doctor if necessary.
NOTICE
Aggressive fluids
- Risk of damage to components and surfaces
-> Do not spill fluids.
-> In the event of contact, wash the component or surface with water.
-> Replace components that are already damaged.
Information
The slightly different illustrations between V8 and V6 show essentially the same actions.
Information
- When lowering the engine, make sure that cables or lines are not trapped accidentally between the engine and body. To prevent this, a second person must make sure that the cables and lines do not get caught.
1. Release electric plug connection -1- - M - on the DME control unit -2- ( -a- ) and pull it off -A-.
Plug connection on DME control unit
2. Loosen fastening nut -1- for ground point at the body and remove ground cable -2- to the DME control unit.
Cut the tie-wrap if necessary.
Ground point on body
3. Remove the tie-wrap -3- if necessary.
4. Open the cover of the front relay box in the plenum panel. -> 970955 Replacing sub-part of wire harness in engine compartment at the front left 970955 Replacing sub-part of wire harness in engine compartment at the left
5. Release and unplug the electric plug connections -1- on the engine wire harness.
Disconnecting plug connections
6. Unclip the engine wire harness -1- in the plenum panel from the retaining clips -2- and remove it.
Engine wire harness in plenum panel
7. Remove B+ transfer point on the left spring dome. To do this, loosen the two positive cables at the pins. Clip in cable on the bulkhead. Lay the cables for the engine. -A and B-
B+ transfer point on left spring dome
8. Disconnect the two coolant lines and the vacuum line on the right side of the engine compartment. -1 to 3- Simply pull off the vacuum line (hold line securely below the connection).
Wiring
8.1. Disconnect the coolant line -1- from the coolant reservoir -2- at the bleeder valve.
Coolant lines at the reservoir
8.2. Loosen the clamp -3- on the coolant hose -4- at the coolant reservoir -2-.
Pull off the coolant hose.
9. Disconnect the four oxygen sensor connectors on the body next to the spring-strut dome on the right and unclip the cables from the holders. -1, 2, 3 and 4- Set down the cables for the engine.
Oxygen sensor connector next to spring-strut dome
10. Drain the hydraulic fluid reservoir -1- and the PDCC reservoir -2- , if necessary, using a suitable tool.
Then remove the hoses -3, 4- at the reservoirs and close them off using suitable stoppers. -> 489719 Removing and installing reservoir - section on "Removing" Service and Repair, -> 430955 Replacing reservoir (PDCC) - section on "Removing" Service and Repair
Hoses for hydraulic reservoir
11. Disconnect fuel line -1- at the transfer point (counter!). Unclip the fuel line at the plenum panel.
Plenum panel lines
12. Release clamped connection -2- on the tank ventilation line.
13. Disconnect the coolant supply and return lines from the radiator. To do this, pull out the securing clip at the upper hose and pull off the connection -1-. The clip should be fitted again immediately to avoid confusion. Undo bottom hose -2-. To do this, undo spring band clamp and pull off hose.
Disconnect the small breather hose from the connection piece. To do this, loosen the spring band clamp.
Coolant hoses
14. Raise the vehicle.
15. Disconnect the ground point on the right longitudinal member. -arrow-
Ground point on right longitudinal member
16. Unscrew fastening screws -1, 2- for holders -3, 4- for brake hydraulic lines.
Holders for hydraulic lines
17. Loosen holders from the wheel bearing housing -5-.
18. Release electric plug connections -1- for the speed sensor on the wheel bearing housing -a- and pull them off -A-.
Plug connections on wheel bearing housing (shown as an example)
19. Remove the brake caliper and suspend it at a suitable position in the wheel arch => Suspending brake caliper (do not open brake hydraulics!).
Also protect the brake caliper (e.g. with a cloth or suitable rubber mat) to prevent damage to the paintwork.
Suspending brake caliper
20. Remove fastening screws -1- for the connecting links -2- at the bottom of the anti-roll bar -3-.
Connecting link for anti-roll bar
21. Press out the ball joint between the wheel carrier and upper wishbone using ball joint puller T10187.
22. Unscrew the fastening screw -2- for the spring strut -3- and at the same time, raise the axle support -1- as far as required using a suitable jack -4- so that the fastening screw can be pushed out easily.
Removing spring strut mounting
23. Loosen the fastening screw -1- on the holder -2- for ATF lines -3- at the thermostat -4-.
ATF lines from thermostat to transmission
24. Place a suitable container underneath to catch emerging ATF.
- Place a suitable panel under the thermostat and allow emerging ATF to flow from the body.
- Pull ATF lines out of the thermostat.
- Close off the ATF lines and bores on the thermostat using suitable stoppers.
25. Loosen the clamping screw -1- on the steering column -2- at the steering gear -3-.
Loosening steering column at the steering gear
Slide the steering column -2- upwards -arrow- and pull it down off the steering gear -3- ( -A- ).
26. Pull clamps -1- off the coolant lines -2- for the heating water heat exchanger in the engine compartment at the rear left on the wheel housing.
Coolant lines in front left wheel housing
27. Pull off coolant hoses -2-.
28. Loosen the cardan shaft at the transfer gear using a mounting lever and tie it up. -> 390219 Removing and installing cardan shaft - section on "Removing" 390219 Removing and installing front cardan shaft
29. Detach heat shield on the right of the transmission. To do this, unscrew three fastening screws -arrows-.
Heat shield
30. Release electric plug connections -1, 2- at the right of the transfer gear -a, b- and pull them off -A, B-.
Plug connections for transfer gear at the right
31. Release electric plug connections -1, 2- at the bottom of the transfer gear -a, b- and pull them off -A, B-.
Plug connections for transfer gear at the bottom
32. Mark gearshift position - N - -1- on the automatic transmission -2- with a suitable pen -A-.
Marking gearshift position
33. Remove shift cable -3- on the automatic transmission -4-. -> 371519 Removing and installing selector lever cable - section on "Removing"
Removing shift cable
33.1. Unclip the cable -3- at the front on the ball joint -1- using disassembly tool Nr.21.
33.2. Unscrew fastening screws -2- at the rear shift cable -3-.
34. Loosen the clamp -1- on the hydraulic line -2- in the front left wheel housing and pull the hose off the hydraulic line.
Front left hydraulic line
Close off the line and connection piece using suitable stoppers.
35. Loosen the fastening screw -1- for the refrigerant line -2- at the front left longitudinal member -3- and pull out the line.
Front left refrigerant line
36. Remove the line -1- from the air-conditioning compressor to the condenser -2-.
Line from air-conditioning compressor to condenser
36.1. To do this, unscrew the fastening screw -3- for the line -1- at the condenser -2-.
36.2. Close off lines and connection pieces.
37. Loosen fastening nuts -8- on the exhaust clamp (clamping sleeve) -3- between the catalytic converter and exhaust system. Slide exhaust clamps onto the exhaust system. The exhaust clamps must not be re-used. -> 260119 Removing and installing exhaust system - section on "Removing" Service and Repair
Loosening clamps
38. Mark the installation position of the front-axle carrier diagonally on at least two places on the body using a felt-tip pen. This makes it easier to correctly position the front-axle carrier on the body during reinstallation.
Marking installation position of front-axle carrier
Information
- Because of the high loosening torque, the six fastening screws on the front-axle carrier can already be loosened now. Loosen the screws by a maximum of one turn.
39. Place the lifting platform under the engine and raise it. When you do this, ensure that the positioning guides of the lifting platform are inserted into the body. => Lifting platform under engine
Lifting platform under engine
40. The -arrows- show the mounting points for the mounting frame in the front-axle carrier (view from below here).
Mounting points for front-axle carrier
41. Position lifting platform in the front-axle carrier in the mounting points provided -(arrows)- , -4 into the body-.
Lifting platform
42. Secure the spring struts. To do this, turn the rubber discs upwards until they are set under the steering knuckle. Then tighten the retaining brackets on the wheel hub and lifting platform. -arrow-
Securing spring struts
43. Loosen the transmission cross member. To do this, loosen the four fastening screws -A-.
Fastening screws for transmission cross member
44. Secure the engine/transmission unit. Then secure the mounting mandrels on the engine transverse bar with the locking screws.
45. Loosen the four fastening screws on the front-axle carrier and the two fastening screws on the engine transverse bar. => Fastening screws on front-axle carrier and fastening screws on engine transverse bar (centre)
Fastening screws on front-axle carrier and fastening screws on engine transverse bar (centre)
46. Lower the lifting platform slowly by approx. 20 to 30 cm. When doing this, a second person should ensure that there is sufficient clearance around the engine compartment and spring struts in the wheel housings.
Information
- Before moving the lifting platform, mark the position of the wheels on the workshop floor with a piece of chalk. This makes it easier to position the platform again for re-installation.
Position of lifting platform
47. Lower the lifting platform fully. When doing this, a second person should ensure that there is sufficient clearance around the engine compartment and wheel housings.