The following steps should always be carried out in the specified order before working in the engine compartment :

Park the vehicle on a level and stable surface.

Depress and hold the brake pedal until the engine has stopped.

Apply the handbrake firmly Braking, stopping and parking Brakes Parking .

Select the neutral position or move the selector lever to P Changing gear Changing gear Automatic gearbox see Automatic gearbox_0 Automatic gearbox see Changing gear_0 Automatic gearbox Manual gearbox see Changing gear_0 Manual gearbox .

Stop the engine and remove the key from the ignition Starting and stopping the engine Engine and ignition Ignition see Engine and ignition_6 .

Allow the engine to cool sufficiently.

Children and other people should be kept well away from the engine compartment.

Ensure that the vehicle cannot roll away unexpectedly.

WARNING
Preparing the vehicle for working in the engine compartment
Opening and closing the bonnetDriving
a loaded vehicle
First read and observe the introductory information
and safety warnings
For good vehicle handling when driving a loaded vehicle, please observe the following:
Stow all items of luggage securely .
Accelerate carefully and gently.
Avoid sudden braking and driving manoeuvres.
...
Wheel, Balancing with Fine Balancing Machine (Finish Balancer)
Before beginning balancing, the following requirements must
be fulfilled.
The tire pressure must be OK.
The tire profile must not be worn on one side. The tire
profile must be at least 4 mm.
...
Oxygen Sensor Unit Protective Pipes
Note
In addition to using the part number, the protective pipe
can also be used for identification.
Version D1, 6 openings, 3.5 mm each
Only used with the 4-pin oxygen sen ...