2021 AUDI A8 engine

Driving

The Start/Stop system is automatically activated
once
the ignition is switched on.
Switching the Start/Stop system off and on
The & button is located above the selector lever
in the center console. The LED in the button turns
on when the function is switched off.
> Press & to switch the system on or off.
If you switch the system off during a Stop phase,
the engine will start again automatically.
Basic requirements
— The driver's door and hood must be closed.
—"P","N", or "D" must be engaged.
— The steering wheel must not be turned far in ei-
ther direction.
— The vehicle must have driven faster than 2 mph
(3 km/h) since the last time it stopped.
— The vehicle is not in trailer mode.
® Note
Always switch the Start/Stop system off when
driving through water > page 118.
G) Tips
— Depending on the driving situation, the en-
gine may already stop when coasting before
the vehicle has come to a complete stop.
— If you select the "D" position after shifting
into reverse, the vehicle must be driven fast-
er than 6 mph (10 km/h) in order for the
Start/Stop system to become active again.
This makes it possible to maneuver without
stopping the engine.
Stopping and starting the engine
Applies to: vehicles with Start/Stop system
> Press and hold the brake pedal until the vehicle
has stopped. The @ indicator light appears in
the instrument cluster once the engine stops
automatically.
> The engine starts again when you remove your
foot from the brake pedal. The indicator light
turns off.
If the parking brake is set, the engine will only
start again when the accelerator pedal is pressed.
118
G) Tips
— Press the brake pedal during a Stop phase
to keep the vehicle from rolling.
— The ignition will turn off if you press the
START ENGINE STOP] button during a Stop
phase.
— If you leave the vehicle briefly during a Stop
phase and then enter again, the driver's
door must be closed and the safety belt
must be fastened in order for the engine to
be able to restart.
— You can control if the engine will stop or not
by reducing or increasing the amount of
force you use to press the brake pedal. For
example, if you only lightly press on the
brake pedal in stop-and-go traffic or when
turning, the engine will not switch off when
the vehicle is stationary. If you press the
brake pedal harder, the engine will switch
off.
Starting and stopping the engine automat-
rely
Applies to: vehicles with Start/Stop system


The system checks if certain conditions are met
before and during the Stop phase, and deter-
mines if the engine stops and how long it re-
mains stopped. For example, if power usage is
high, the engine will not be stopped. Along with
other conditions, the following factors influence
the automatic engine start or stop:
— Environmental conditions (slopes, inclines, ele-
vation, temperature)
— Battery (charge status, temperature, power us-
age)
— Engine temperature
— Assist systems
— Driving behavior
Depending on the engine, the indicator light
may appear if the engine is not stopped.
Applies to: vehicles with Start/Stop system
Drive system: please start the vehicle manually >

4N0012721BF
Driving

This message appears when specific conditions
are not met during a Stop phase. The Start/Stop
system will not be able to restart the engine. The
engine must be started with the
START ENGINE STOP] button.


Vehicle starting system: malfunction! Please
contact Service
There is a malfunction in the Start/Stop system.
Drive the vehicle to an authorized Audi dealer or
authorized Service Facility as soon as possible to
have the malfunction corrected.
Brakes
General information
You can apply the vehicle's brakes using the brake
pedal.
Operating noise
Noises may occur when braking depending on the
speed, braking force, and outside conditions such
as temperature and humidity.
Braking effect
The response time from the brakes depends on
the weather and environmental conditions. To
ensure the optimal braking effect, the brake sys-
tem is cleaned at regular intervals. This is done
by applying the brake pads to the brake rotors for
a short period of time when driving at high
speeds when the windshield wipers are switched
on.
If the brake system becomes damp, for example
after driving in heavy rain, the braking effect may
be delayed. Other factors that could temporarily
increase the response time of the brakes include:
— Wet conditions
— Low temperatures, ice, and snow
— Roads covered in salt
— Dirty brake pads
Corrosion
Corrosion may form on the brake rotors if there is
no heavy braking, if the vehicle is not driven for
long periods of time, or if the vehicle is not driv-
en
frequently or for long distances. In this case,
braking heavily several times while driving at
high speeds can clean the brake rotors > A\.
Applies to: vehicles with plug-in hybrid drive: Se-
lect the “N” gear so that recuperation is not used
for braking.
Brake pads
New brake pads do not achieve their full braking
effect during the first 250 miles (400 km). They
must be “broken in” first. However, you can com-
pensate for the slightly reduced braking force by
pressing firmly on the brake pedal. Avoid heavy
braking during the break-in period.
Applies to: vehicles with plug-in hybrid drive: Be-
cause recuperation is also used for braking, the
break-in period for new brake pads is 500 miles
(800 km).
Brake pad wear depends largely on the way the
vehicle is driven and on operating conditions.
Brake pad wear increases when driving frequently
in the city or short distances or when using a very
sporty driving style.
Ceramic brakes
Applies to: vehicles with ceramic brakes
Ceramic brakes provide excellent deceleration
rates.
The break-in period for new ceramic brakes may
be significantly longer than for standard brake
rotors. Due to the properties of the material,
they may cause noises at lower speeds. Ceramic
brakes also absorb more moisture in wet condi-
tions. Therefore, there will temporarily be less
braking force than when the brakes are dry. You
can compensate for this by pressing the brake
pedal harder.
Automatic post-collision braking system
The automatic post-collision braking system can
help to reduce the risk of sliding and of addition-
al collisions after an accident. If the airbag con-
trol module detects a collision, the vehicle is
braked by the ESC.
The vehicle does not brake automatically if one of
the following occurs:
— The driver presses the accelerator pedal, or >
119

Driving

— The braking force generated by the pressed
brake pedal is greater than the braking force
that
would be initiated by the system
— The ESC, the brake system, or the vehicle elec-
trical system is not functioning

ZA WARNING
— Only apply the brakes for the purpose of
cleaning the brake system when road and
traffic conditions permit. You must not en-
danger other road users and increase the
risk of an accident.
— Due to the risk of injury, only have an au-
thorized Audi dealer or authorized Audi
Service Facility work on the brake system.
Incorrect repairs could impair the function.
— Never let the vehicle roll while the engine is
stopped because this increases the risk of an
accident.
— During automatic braking maneuvers, the
brake pedal may move downward automati-
cally. To reduce the risk of injury, do not
place your foot under the brake pedal.
@) Note
— Never let the brakes “rub” by pressing the
pedal lightly when braking is not actually
necessary. This can cause the brakes to over-
heat and increases braking distance and
causes wear.
— Observe the important information for driv-
ing downhill > page 122. This especially ap-
plies when towing a trailer.
G@) Tips
— If you retrofit your vehicle with a front spoil-
er, wheel covers or similar items, make sure
that the air flow to the brakes is not ob-
structed. Otherwise the brake system can
overheat.

— Also refer to the information about brake
fluid > page 283.
Messages
GG i @ Brakes: malfunction! Stop vehicle
safely
120
There is a malfunction in the brake system. If
[S/ Bana B also turn on, there is a malfunc-
tion in the ABS, ESC, and braking distribution. If
the brake booster is not working, you have to use
much more force when braking the vehicle.
Do not continue driving. See an authorized Audi
dealer or authorized Audi Service Facility for as-
sistance. Read and follow the other safety pre-
cautions > A\.
fie 7 © Brake pads: wear limit reached. You
can continue driving. Please contact Service
The brake pads are worn. Drive to an authorized
Audi dealer or authorized Audi Service Facility as
soon as possible to have the malfunction correct-
ed.
Brake booster: limited functionality. You can
continue driving. Please contact Service
There is a brake booster malfunction. The brake
booster is available, but its effectiveness is re-
duced. The braking performance may be different
compared to the usual performance. Drive to an
authorized Audi dealer or authorized Audi Service
Facility immediately to have the malfunction cor-
rected.
Brake booster: deactivated. See owner's manual
The brake booster remains active for a brief peri-
od of time after switching off the ignition. Secure
the vehicle against rolling > page 108.
Other indicator lights
When you switch the ignition on, the GG / @®
indicator light turns on briefly to check the func-
tion. If the indicator light does not turn on, there
is a system malfunction.
1f Ba / @ stays on, there is a malfunction in
the brake system.
@- A high load was placed on the brakes from
driving downhill for a long period of time. Follow
the instructions in the message to utilize the en-
gine braking effect and to relieve the brakes.

ZA WARNING
If a malfunction occurs in the ABS, ESC, and
braking distribution, interventions that >

Driving


ZA\ WARNING
Heavy braking while driving through curves or
in poor road or weather conditions can cause
the vehicle to slide or the rear of the vehicle to
swerve, which increases the risk of an acci-
dent.
Messages
ERNG / B) Parking brake: malfunction! Safely
stop vehicle. See owner's manual
Gg / © Parking brake: malfunction! Please
release parking brake

If one of the two messages appears, there is a
malfunction in the parking brake. If the message
appears while stationary, check if the parking
brake is released and can be reset. If this is the
case, switch the ignition off and back on.
If the message stays on, if the parking brake can-
not be released, or if the message appears while
driving, do not continue driving. Secure the vehi-
cle against rolling before exiting the vehicle
= page 108. See an authorized Audi dealer or au-
thorized Audi Service Facility for assistance.
we Parking brake: malfunction! Please contact
Service
There is a malfunction in the parking brake. Drive
to an authorized Audi dealer or authorized Audi
Service Facility immediately to have the malfunc-
tion corrected. Do not park the vehicle on inclines
and shift to “P”.
a / Parking brake: warning! Vehicle parked
too steep
The braking force may not be enough to secure
the vehicle from rolling away. Park the vehicle in
a place with less of an incline.
FS / () Parking brake: applied
The parking brake is set. Press and hold the brake
pedal to release the parking brake.
122
Special driving situations
Driving uphill and downhill
When driving uphill, downhill, or at high alti-
tudes, note the following information:
— Drive slowly and carefully.
— Do not try to turn around if you cannot safely
drive on an incline or hill. Instead, drive in re-
verse.
— When driving down hills, you can activate the
hill descent control if you press the brake pedal
while driving in “D” gear. The automatic trans-
mission will select a gear suitable for driving
down the hill and will attempt to maintain the
speed at which the vehicle was traveling at the
time the brake pedal was pressed. Press the
brake pedal if necessary. The hill descent con-
trol will switch off once the hill levels out or
you press the accelerator pedal.
— Utilize the engine braking effect when driving
downhill by selecting the “S” driving program
= page 110. This especially applies when tow-
ing a trailer. This reduces the load on the
brakes.
— Apply the brakes in intervals and do not press
the brake pedal continuously.

ZA\ WARNING
— Only drive on inclines that your vehicle is de-
signed to handle. Do not exceed the hill
climbing ability of your vehicle. Your vehicle
could tip or slide.
— Do not drive at an angle on steep inclines
and hills. If your vehicle is about to tip, you
must immediately start steering in the di-
rection of the downward slope to reduce the
risk of an accident.
— Always be ready to brake when using the hill
descent control function.
Driving through water
If you must drive through water, follow these in-
structions:

— Check the stability of the ground, the current,
and the water depth. If the ground is unstable,
there is a strong current, or there are waves, >

4N0012721BF
Driving

the water must only reach up to the lower edge
of the body at the most.
— Deactivate the Start/Stop system.
— Drive carefully and no faster than at walking
speeds to prevent the front of the vehicle from
creating waves, because they could splash
above the lower edge of the body. Oncoming
vehicles could also create waves.
— Do not stop the vehicle while in the water.
— Drive in reverse.
— Do not turn the engine off.

After driving through water, press the brake
pedal carefully to dry the brakes so that the
full braking effect will be restored.

Vehicle components such as the engine, drive
system, suspension, or electrical system can
be severely damaged by driving through wa-
dele,
If possible, avoid driving through salt water
because it increases the risk of corrosion. Use
fresh water to clean any vehicle components
that come into contact with salt water.
123

Driving dynamic

Driving dynamic
Audi drive select
Introduction
Applies to: vehicles with Audi drive select
Drive select makes it possible to experience dif-
ferent types of vehicle characteristics in one vehi-
cle. With different driving modes, the driver can
switch the setting, for example from sporty to
comfortable. This allows you to adjust the set-
tings to your personal preferences. This makes it
possible to combine settings such as a sporty
drivetrain setting with comfortable steering.
Selecting an Audi drive select mode
Applies to: vehicles with Audi drive select
The sie button is located above the selector lever
in the center console.
> Press the left or right arrow key until the de-
sired mode appears in the MMI. Or:
» Applies to MMI: Select on the home screen: VE-
HICLE > Audi drive select.
You can change the driving mode when the vehi-
cle is stationary or while driving. If traffic per-
mits, briefly remove your foot from the accelera-
tor pedal after changing modes so that the mode
you have selected will be activated for the drive
system.
The following modes may be available depending
on the equipment:
comfort - Provides a comfort-oriented vehicle
setup and is suited for long drives on highways.
comfort+ - Provides a comfort-oriented vehicle
setup and switches on the curve tilting function
in the active suspension system. This mode is
suitable for long trips on highways and smooth
driving around curves, for example.
auto - Provides an overall comfortable yet dy-
namic driving feel and is suited for everyday use.
dynamic - Gives the driver a sporty driving feel
and is suited to a sporty driving style. The “S”
driving program is selected.
124
Individual - Provides the option for personalized
vehicle settings. Press &% to configure the mode
= page 124, Individual settings.
G) Tips
When the ignition is being switched on, indi-
vidual systems, such as the drive system, will
be reset to a balanced setting. Select the cur-
rent mode again to attain its full configura-
tion.
Individual settings
Applies to: vehicles with Audi drive select
The equipment in your vehicle will determine
which settings you can adjust.
Drive
The drive system will react to accelerator pedal
moves more quickly or in a more balanced man-
ner. The shift points are placed in higher or lower
speed ranges.
Depending on the setting, the drive power at the
rear axle will be distributed with the sport differ-
ential* to be more sporty or moderate
=> page 128.
Steering
The power steering will adapt. Light steering is
suitable for long trips on highways or smooth
driving around curves, for example.
Suspension
The suspension adjusts to be tighter or more
comfort-oriented when it comes to compensat-
ing for uneven spots on the road.
Based on the selected setting, the air suspen-
sion* will adjust the ground clearance and the ac-
tive suspension* will provide various degrees of
compensation for vehicle movements.
Engine sound
The engine sound adapts and can be subtle to
sporty. In the automatic setting, the engine
sound depends on the selected driving program.

Driving dynamic

Applies to: vehicles with elevated entry
With the Elevated entry function, you can select
if the vehicle should be raised when a door is
opened in order to enter and exit the vehicle
more comfortably. The vehicle will lower again
slowly in the following situations:
— When starting from a stop
— When locking the vehicle
— When changing the Audi drive select* mode
— Approximately 10 seconds after all doors have
been closed
— After a certain period of time when the engine
is stopped and a door is open, in order to main-
tain the battery charge level.
This function may not be available under certain
conditions, for example if the ground is not level
or when the battery charge level is low. The func-
tion may also be deactivated temporarily after
the vehicle is serviced using diagnostic equip-
ment, and it will only be available again once the
vehicle is driven a certain distance.
@ Note
When the elevated entry function is activated,
make sure there is sufficient space above and
below the vehicle. This particularly applies to
space under open doors and above roof struc-
tures. If you are unsure about the amount of
space, deactivate the elevated entry function
before exiting the vehicle to reduce the risk of
damage.
@) Tips
— If an open door touches the ground or be-
comes stuck, use the Raise > page 125
function in the MMI to raise the vehicle us-
ing the air suspension.
— When the curve tilting function is switched
on, the vehicle passengers will experience
less turning force when driving around
curves. This may influence the perception of
speed. Always adjust the speed to the driv-
ing situation.
126
Ground clearance
The vehicle height and clearance can be influ-
enced by the following factors:
— Change in temperature
— Change in load
— Change to the Audi drive select* mode
— Lifting and lowering via the air suspension*
— Automatic lifting and lowering using the Ele-
vated entry* function

ZA\ WARNING
To reduce the risk of injury, make sure no one
gets pinched when the vehicle level is chang-
ing, for example when cleaning the under-
body or the wheel housings.
@) Note
Always make sure there is enough clearance
above and below the vehicle. This is especially
important for entrances with height restric-
tions, for example, before driving into under-
ground garages. You could also scrape the
ground when driving over the edges of curbs
or on steep ramps, which could damage your
vehicle.
B Air suspension: malfunction! You may con-
tinue driving slowly at max. XX mph (km/h)

There is a malfunction. Driving stability may be
limited. Drive to an authorized Audi dealer or au-
thorized Audi Service Facility immediately. Do not
drive faster than the speed given in the message.
B Air suspension: malfunction! Safely stop ve-
hicle. Steering and ground clearance limited
There is a malfunction. Do not continue driving.
Secure the vehicle against rolling before exiting
the vehicle > page 108. Avoid turning the steer-
ing wheel, because the vehicle ground clearance
may be so low that turning the steering wheel
could result in damage to the wheels and wheel
housings.
B Active suspension: unavailable. Limited sta-
bility. You can continue driving with caution >

Driving dynamic

There is a malfunction in the electronic steering
lock. You cannot turn the ignition on. Secure the
vehicle against rolling before exiting the vehicle
=> page 108. Do not tow your vehicle because it
cannot be steered. See an authorized Audi dealer
or authorized Audi Service Facility for assistance.
a Steering: malfunction! You can continue
driving
There is a malfunction in the steering system.
Steering may be more difficult or more sensitive.
Adapt your driving style. Have the steering sys-
tem checked immediately by an authorized Audi
dealer or authorized Audi Service Facility. Please
note that the red indicator light may turn on af-
ter restarting the engine. Do not continue driving
if it does.
& Steering: malfunction! Adapt driving style.
Larger turning radius
The rear axle steering may have failed. The vehi-
cle will have a larger turning radius, and the sta-
bility when driving around curves will be compa-
rable to a vehicle without rear axle steering. Drive
carefully to an authorized Audi dealer or author-
ized Audi Service Facility to have the malfunction
corrected.
BS Steering lock: malfunction! Please contact
Service
There is a malfunction in the electronic steering
lock. Drive immediately to an authorized Audi
dealer or authorized Audi Service Facility to have
the malfunction repaired.
Dynamic steering: correcting steering wheel
position
The steering is reinitializing. The steering wheel
will move easily after starting the vehicle. Reiniti-
alization might be necessary if the steering wheel
was moved while the engine was switched off.
The display turns off if the initialization was suc-
cessful.

ZX WARNING
Do not tow your vehicle if there is a malfunc-
tion in the electronic steering lock because
this increases the risk of an accident.

128
G) Tips
— If there is a malfunction, the steering wheel
may be crooked when driving straight.
—If the a or & indicator light only stays on
for a short time, you may continue driving.
All wheel drive (quattro)
Applies to: vehicles with all wheel drive
The all-wheel drive system distributes the driving
power variably to the front and rear axle to im-
prove the driving characteristics. It works togeth-
er with selective wheel torque control, which can
activate when driving through curves
=> page 129.
The all-wheel drive system is designed for high
engine power. Your vehicle is exceptionally pow-
erful and has excellent driving characteristics
both under normal driving conditions and on
snow and ice. Always read and follow safety pre-
cautions > A\.

Z\ WARNING
— Even in vehicles with all wheel drive, you
should adapt your driving style to the cur-
rent road and traffic conditions to reduce
the risk of an accident.
— The braking ability of your vehicle is limited
to the traction of the wheels. In this way, it
is not different from a two wheel drive vehi-
cle. Do not drive too fast because this in-
creases the risk of an accident.
— Note that on wet streets, the front wheels
can “hydroplane’” if driving at speeds that
are too high. Unlike front wheel drive
vehicles, the engine RPM does not increase
suddenly when the vehicle begins hydro-
planing. Adapt your speed to the road condi-
tions to reduce the risk of an accident.
Sylar)
Applies to: vehicles with sport differential

The sport differential distributes the drive power
to the rear axle based on the situation. The goal
is a high level of agility and ability to accelerate >