2021 AUDI A8 service

Checking and Filling

corrosion damage and damage to plastic or
rubber components in the fuel system.
— Do not use gasoline that does not meet the
specifications.
— If you are unable to find out if a specific gas-
oline mixture meets the specifications, ask
the gas station operator or their fuel suppli-
er.
— Do not use any gasoline mixture whose
composition cannot be identified.
— Audi does not assume any responsibility for
damage to the fuel system or for perform-
ance problems caused by using gasoline
mixtures different from those specified.
This type of damage also does not fall under
the New Vehicle Limited Warranty or under
the emissions control system warranty.
— If you notice a higher fuel consumption or
poor handling or performance problems due
to such gasoline mixtures, Audi recom-
mends fueling with unblended gasoline.
Gasoline additives
An important issue for many automobile manu-
facturers is combustion residue in the engine
that results from the use of certain fuels.
Although types of gasoline differ depending on
the manufacturer, there are similarities. Certain
substances in the gasoline may cause deposits in
the engine. Additives in the gasoline that should
keep the engine and fuel system clean do not all
function equally.
Audi recommends using TOP TIER Detergent Gas-
oline. For additional information on TOP TIER De-
tergent Gasoline, visit www.toptiergas.com.
If you use incorrect fuels over a long period of
time, the maximum engine performance may be
impaired by combustion residue.
@) Note
— Damage or malfunctions caused by the use
of incorrect types of gasoline are not cov-
ered by the New Vehicle Limited Warranty.
— Only gasoline additives that have been ap-
proved by Audi may be used.
270
Refueling
Messages
A Tank system: malfunction! Please contact
Service
There is a malfunction in the fuel tank system.
Drive to an authorized Audi dealer or authorized
Audi Service Facility immediately to have the
malfunction corrected.
Messages
Applies to: vehicles with plug-in hybrid drive
A Fuel filler door: malfunction! Unlock fuel
filler door manually. See owner's manual
There is a malfunction. You must manually un-
lock the fuel filler door > page 273.
Al Warning! Vehicle performance may be limit-
ed
The fuel tank is almost empty. You must antici-
pate a significant power loss. Refuel immediate-
ly.
& Please refuel and charge battery. Total
range: x mi (km)
or
f& Tank system: please refuel immediately and
charge battery. Total range: x mi (km)
If this indicator light turns on and this message
appears, refuel as soon as possible. Otherwise,
the high-voltage battery is drained > page 131.
AY Fuel filler door open. Please press button
again to refuel
Fueling is possible for a little while after pressing
the G) button. You must press the A button
again if the time limit is exceeded.

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Checking and Filling

Fuel filler door emergency release
Applies to: vehicles with manual fuel filler door release

If the central locking system malfunctions, the
fuel filler door can be unlocked manually.



Fig. 177 Right cover in the luggage compartment: remov-
ing the cover



Fig. 178 Luggage compartment: fuel filler door emergency
release
The emergency opening mechanism is located
behind the right cover in the luggage compart-
ment.
> Remove the screwdriver from the vehicle tool
kit > page 317.
> Carefully insert the flat side of the screwdriver
from below into the center of the top slot in the
cover > fig. 177.
> Use the screwdriver to pull the cover toward the
center of the vehicle and remove the cover.
> To unlock the fuel filler door, loosen the red
loop from the retainer and then pull on the
loop carefully > fig. 178 > ©.
> Press on the left side of the fuel filler door to
open it > page 271, fig. 175.
® Note
Only pull on the loop until you feel resistance.
You
will not hear it release. If you continue to
pull, you could damage the emergency re-
lease mechanism.
@ Tips
Applies to: vehicles with plug-in hybrid drive
— The tank will not be vented if the emergency
release function was used on the fuel filler
door. You can only fill a small amount of
fuel in the tank. Fill only until the fuel pump
nozzle turns off for the first time. Drive to
an authorized Audi dealer or authorized
Audi Service Facility immediately to have
the malfunction corrected.
— Pressure can escape if you open the tank cap
after using the emergency release. This can
create noises.
Emissions control
system
General information
ZA\ WARNING
The temperature of the exhaust system is
high, both when driving and after stopping
the engine.
— Never touch the exhaust tail pipes once they
have
become hot. This could result in burns.
— Do not park your vehicle over flammable
materials such as grass or leaves because
the high temperature of the emissions sys-
tem could start a fire.
— Do not apply underbody protectant in the
exhaust system area, because this increases
the risk of fire.
Catalytic converter
Observe the safety precautions > page 273, Gen-
eral information.


The vehicle may only be driven with unleaded
gasoline, or the catalytic converter will be de-
stroyed.
Never drive until the tank is completely empty.
The irregular supply of fuel that results from that
can cause engine misfires. Uncombusted fuel
could enter the exhaust system, which could >
273

Checking and Filling

cause overheating and damage to the catalytic
converter.
Malfunction Indicator Lamp (MIL)
If the S indicator light blinks or turns on, there
is a malfunction that is causing poor emissions
quality and that could damage the catalytic con-
verter. Drive slowly to an authorized Audi dealer
or authorized Audi Service Facility to have the
malfunction corrected.
The indicator light can also turn on if the fuel fill-
er cap is not closed correctly > page 271).
Engine compartment
General information
Special care is required if you are working in the
engine compartment
For work in the engine compartment, such as
checking and filling fluids, there is a risk of in-
jury, scalding, accidents, and burns. For this
reason, follow all the warnings and general
safety precautions provided in the following in-
formation. The engine compartment is a dan-
gerous area in the vehicle. > A.
Explanation of warnings (sticker in the engine
compartment):
®

Hot engine components!
Rotating parts!

The catalytic converter can be damaged
"127i if the oil level is too high!

Always follow the instructions in the op-
oA erating manual.



The radiator fan can switch on at any
i, time!

High voltage! Switch off the engine be-
5 fore coming into contact with any igni-
tion system components!



Applies to: vehicles with plug-in hybrid
drive: High voltage! The voltage in the
high-voltage system is high enough to
EN cause fatal injuries. Touching a damaged
high-voltage component can result in a
fatal electric shock.


D_ Depending on the engine and country
274

ZA\ WARNING
— Turn the engine off.
— Switch the ignition off.
— Set the parking brake.
— Select the “P” (Park) selector lever position.
— Allow the engine to cool.
— Keep children away from the engine com-
partment.
— Never spill fluids on a hot engine. These flu-
ids (such as the freeze protection contained
in the coolant) can catch fire.
— Avoid short circuits in the electrical system.
— Never reach into the radiator fan. The fan is
temperature-controlled and can turn on
suddenly, even when the ignition is switched
off.
— Never open the hood when there is steam or
coolant escaping from the engine compart-
ment, because there is a risk that you could
be burned. Wait until no steam or coolant is
escaping.
— Plug-in hybrid drive: The coolant expansion
tank cap is equipped with a seal that must
never be removed under any circumstances
= page 277, fig. 181. If the coolant expan-
sion tank for the high-voltage system is not
sealed, please contact an authorized Audi
dealer or authorized Audi Service Facility.
— Plug-in hybrid drive: The sealed cap must
only be opened by an authorized Audi dealer
or authorized Audi Service Facility.
—The cap on the coolant expansion tank must
never be opened when the coolant is hot.
The cooling system is under pressure. There
is a risk of burns
—To protect your face, hands, and arms from
hot steam or coolant, cover the cap with a
thick cloth when opening.

4N0012721BF
Checking and Filling


— Do not remove the engine cover under any
circumstances. This increases the risk of
burns.
— Due to the risk of electric shock, never touch
the ignition cable or other components in
the electronic high-voltage ignition system
when the engine is running or is starting.
— If a gear is engaged while the vehicle is sta-
tionary and the engine is running, do not
press the accelerator pedal inadvertently.
Pressing the accelerator pedal will cause the
vehicle to move, and this could result in an
accident.
— If inspections or repairs must be performed
while the engine is running, moving compo-
nents (such as the ribbed belt, generator,
and radiator fan) pose an additional risk.
— Set the parking brake first and select the
“P” (Park) selector lever position.
— Always make sure that no parts of the
body, jewelry, ties, loose clothing, and
long hair can be caught in moving engine
components. Before any work, always re-
move any jewelry and/or ties, tie back long
hair, and make sure all clothing fits close
to the body to reduce the risk of anything
becoming caught in engine components.
— Pay attention to the following warnings list-
ed when work on the fuel system or on the
electrical equipment is required.
— Do not smoke.
— Never work near open flames.
— Always have a working fire extinguisher
nearby.
— All work on the battery or electrical system
in your vehicle can result in injuries, chemi-
cal burns, accidents, or burns. Because of
this, all work must be performed only by an
authorized Audi dealer or authorized Audi
Service Facility.
— Limit your exposure to exhaust and chemi-
cals to as short a time as possible.

emit chemicals known to the State of Cali-
fornia to cause cancer and birth defects and
reproductive harm. In addition, certain flu-
ids contained in vehicles and certain prod-
ucts of component wear contain or emit
chemicals known to the State of California
to cause cancer and birth defects or other
reproductive harm.
— Battery posts, terminals and related acces-
sories contain lead and lead compounds,
chemicals known to the State of California
to cause cancer and reproductive harms.
Wash hands after handling.



ZA WARNING
California Proposition 65 Warning:
— Engine exhaust, some of its constituents,
and certain vehicle components contain or

@) Note
When filling fluids, be sure not to add any flu-
ids to the wrong reservoirs. Otherwise severe
malfunctions and engine damage will occur.
@) For the sake of the environment
You should regularly check the ground under
your vehicle in order to detect leaks quickly. If
there are visible spots from oil or other fluids,
bring your vehicle to an authorized Audi deal-
er or authorized Audi Service Facility to be
checked.
275

Checking and Filling

For more information on the correct engine oil
for your vehicle, contact an authorized Audi deal-
er or authorized Audi Service Facility. Have the oil
changed by an authorized Audi dealer or author-
ized Service Facility.
Gi) Tips
Audi recommends using engine oils provided
by Audi Genuine Parts.
Messages
Engine oil pressure
= Turn off engine. Oil pressure too low
Stop driving and switch the engine off. Check the
engine oil level > page 278.
— If the engine oil level is too low, add engine oil
=> page 279. Only continue driving once the in-
dicator light turns off.
—If the engine oil level is correct and the indica-
tor light still turns on, turn the engine off and
do not continue driving. See an authorized Audi
dealer or authorized Audi Service Facility for as-
sistance.
Engine oil level
2 Please add oil immediately.
Stop driving and switch the engine off. Check the
engine oil level > page 278 and add engine oil
immediately > page 279.
3 Add max. x qt (x J) oil. You can continue
driving
Add the amount of oil shown immediately
=> page 279.
Reducing the oil level
= Please reduce oil level
There is too much oil in the engine and there is a
risk of damaging the catalytic converter or en-
gine. Drive to an authorized Audi dealer or au-
thorized Audi Service Facility immediately to have
engine oil extracted if necessary. Avoid high en-
gine speeds, full acceleration, and heavy engine
loads.
278
Engine oil sensor
=) Oil level sensor: oil change necessary. Please
contact Service
Fuel has entered the engine oil. This will cause
the engine oil level to rise slowly and the engine
oil quality to decrease. Do not extract engine oil
to reduce the level, because this will increase the
risk of engine damage. Drive to an authorized
Audi dealer or authorized Audi Service Facility im-
mediately to have engine oil extracted.
& Oil level system: malfunction! Please con-
tact Service
The sensor that checks the engine oil level has
malfunctioned. Drive immediately to an author-
ized Audi dealer or authorized Audi Service Facili-
ty to have the malfunction repaired.
2 Oil pressure sensor: malfunction! Please
contact Service
The sensor that checks the engine oil pressure
has malfunctioned. Drive immediately to an au-
thorized Audi dealer or authorized Audi Service
Facility to have the malfunction repaired.
Engine warm-up request
i Please drive to warm up engine
Fuel has entered the engine oil, either due to low
outside temperatures or frequent short drives.
Drive until the engine is warm so that the fuel in
the engine oil will evaporate. Avoid high engine
speeds, full accelerating, and heavy engine loads
when doing this.
@) Tips
The oil pressure warning B is not an oil level
indicator. Always check the oil level regularly.
Checking the engine oil level
The engine oil level can be checked in the MMI.
Observe the safety precautions > page 274, Gen-
eral information.
> Park the vehicle on a level surface.
> Shut the engine off when it is warm.
>» Switch only the ignition back on.

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Checking and Filling

> Wait approximately two minutes.
» Applies to MMI: Select on the home screen: VE-
HICLE > Settings & Service > Oil level.
> Read the oil level in the display. Add engine oil
if the bar in the oil level indicator is just below
“min” > page 279.
@) Note
If the engine oil level is too low or too high,
there is a risk of engine damage.
@) Tips
The oil level indicator in the display is only an
informational display. If the oil level is too
low, a minimum oil warning appears in the in-
strument cluster. Add oil and close the hood.
The current oil level will be displayed on the
MMI the next time the ignition is switched on.
@) Tips
The engine oil consumption may be up to
0.5 quart/600 miles (0.5 liter/1,000 km), de-
pending on driving style and operating condi-
tions. Consumption may be higher during the
first 3,000 miles (5,000 km). The engine oil
level must be checked regularly. It is best to
check each time you refuel your vehicle and
before long drives.
— Because of the lubrication and cooling of
the engine, combustion engines consume
oil. The oil consumption varies depending
on the engine and may change during the
service life of the engine. Engines generally
consume more oil at the beginning during
the break-in period. Then oil consumption
stabilizes after the break-in period.
— Under normal conditions, oil consumption
depends on the quality and viscosity of the
oil, the engine RPM, the climate conditions,
and the road conditions. The dilution of oil
from condensation or fuel residue as well as
the age of the oil also play a role. Because
engine wear increases with mileage, oil con-
sumption will increase again over time until
it may be necessary to replace worn compo-
nents.
— Because all these variables play a role, it is
not possible to define an oil consumption
standard. Therefore, the oil level must be
checked regularly.
— If you believe that your engine has in-
creased its oil consumption, contact an au-
thorized Audi dealer or authorized Audi
Service Facility to determine the cause.
Please note that an exact oil consumption
measurement must be done with the neces-
sary care and accuracy and may take time.
An authorized Audi dealer or authorized
Audi Service Facility is trained in accurately
measuring the oil consumption.
— You can find information on engine oil and
engine oil capacities for the USA at www.
audiusa.com/help/maintenance, or for Can-
ada at www.audi.ca/ca/web/en/
customer-area/care-and-maintenance/
audi-service-schedules.html, or call
800-822-2834.
Adding engine oil

RAZ-0013|


Fig. 182 Engine compartment: engine oil filling opening
cover (example)
Observe the safety precautions > page 274, Gen-
eral information.
> Turn the engine off.
> Open the hood > page 276.
>» Unscrew the cap %~ for the engine oil filler
opening > fig. 182.
> Carefully add 0.5 quart (0.5 liter) of the correct
oil > page 277.
> Close the engine oil filler opening cap.
> Close the hood > page 276.
> Restart the ignition after two minutes and read
the current oil level in the MMI > page 278,
Checking the engine oil level.
279

Checking and Filling

» Applies to: using engine oil that meets the rec-
ommended specification: Add some more en-
gine oil again if necessary.

ZA\ WARNING
— When adding oil, do not let oil drip onto hot
engine components. This increases the risk
of a fire.
— You must close the cap on the oil filler open-
ing correctly so that oil does not leak out on-
to the hot engine and exhaust system when
the engine is running, because this is a fire
hazard.
— Always clean skin thoroughly if it comes into
contact with engine oil.
—
Engine oil is poisonous and must be kept out
of reach of children.
— Store the engine oil securely in the original
container.

® Note
— The New Vehicle Limited Warranty does not
cover damage or malfunctions if the recom-
mended intended use of the vehicle and
maintenance measures listed in the Audi
Owner's Manual and the Warranty & Main-
tenance Booklet were not followed.
— Only use high-grade engine oil that explicit-
ly meets the Audi oil quality standard for
your vehicle. Using another oil may cause
severe vehicle damage.
— Do not mix any additives with the engine oil.
Additives may cause engine damage that is
not covered by your New Vehicle Limited
Warranty.
@ For the sake of the environment
— Oil should never enter the sewer system or
come into contact with the ground.
— Follow the legal regulations in the country
where you are located when disposing of
empty oil containers.
280
Changing engine oil
Audi recommends having the oil changed at an
authorized Audi dealer or authorized Audi Serv-
ice Facility.
Observe the safety precautions > page 274, Gen-
eral information.
The engine oil must be changed at the intervals
specified in the Warranty & Maintenance Book-
let. This is very important because the lubrication
function of the oil gradually declines during regu-
lar vehicle operation.
The engine oil should be changed more frequent-
ly under certain circumstances. Have the oil
changed more frequently if you often drive short
distances, your vehicle is predominantly in stop-
and-go traffic situations, is in very dusty environ-
ments, or is operated for long periods of time in
temperatures below zero.
Cleansing additives in the oil make fresh oil ap-
pear darker after the engine has run briefly. This
is normal and no reason to change the engine oil
more frequently than recommended.
Because correctly disposing of engine oil is diffi-
cult and special tools and technical knowledge
are needed for an oil change, Audi recommends
having your engine oil changed by an authorized
Audi dealer or authorized Audi Service Facility.
If you change the engine oil yourself, please note
the following important information:

Z\ WARNING
If you change the engine oil on the vehicle
yourself, the following precautions must be
followed:
— Wear protective eyewear.
— Due to the risk of scalding, allow the engine
to cool down sufficiently.
— Maintain enough distance when you are re-
moving the oil drain plug. While doing this,
keep your forearm parallel to the ground to
reduce the risk of hot oil dripping down your
arm. >

4N0012721BF
Checking and Filling


— Drain the oil into a container designed for
this purpose that is large enough to hold the
full amount of oil in your engine.
— Engine oil is poisonous. Always store out of
reach of children.
— Prolonged contact of used engine oil with
the skin may cause skin damage. Always
wash oil off immediately with soap and wa-
ter to protect your skin.
@) Note
Do not mix any additives with the engine oil.
Additives may cause engine damage that is
not covered by your New Vehicle Limited War-
ranty.

@ For the sake of the environment
— Before changing the engine oil, make sure
you can dispose of the used engine oil cor-
rectly.
— Engine oil must always be disposed of cor-
rectly. Do not dump it in the yard, in the for-
est, or in open water, river channels, or sew-
ers.
— Have your used engine oil recycled by bring-
ing it to a used oil collection site or contact
a gas station.
Cooling system
The engine cooling system is filled with a mixture
of purified water and coolant additive at the fac-
tory. This coolant must not be not changed.
The coolant level is monitored using the Bg indi-
cator light. However, occasionally checking the
coolant level is recommended.
Messages
g& Turn off engine and check coolant level. See
owner's manual
The coolant level is too low.
Stop driving and switch the engine off. Check the
coolant level > page 282.
— If the coolant level is too low, add coolant
=> page 282. Only continue driving once the in-
dicator light turns off.
|_| Coolant temperature: too high. Please let
engine run while vehicle is stationary
Let the engine run at idle for a few minutes to
cool off, until the indicator light turns off.
— If the indicator light does not turn off, do not
continue driving the vehicle. See an authorized
Audi dealer or authorized Audi Service Facility
for assistance.
if Coolant system: malfunction! Please turn
off engine
Do not continue driving, shut the engine off, and
switch the ignition off.
— See an authorized Audi dealer or authorized
Audi Service Facility for assistance.
Applies to: vehicles with plug-in hybrid drive
B Electric drive: malfunction! Cooling system.
Please contact Service
There is a malfunction in the cooling system.
Drive to an authorized Audi dealer or authorized
Audi Service Facility immediately.
Coolant additive
The coolant additive is made of anti-freezing and
corrosion protection agents. Only add the follow-
ing coolant additives mixed with distilled water.

Coolant additive
Gl12evo
Specification
TL774L


The amount of coolant additive that needs to be
mixed with water depends on the climate where
the vehicle will be operated. If the coolant addi-
tive percentage is too low, the coolant can freeze
and damage the engine.


Coolant Freeze protec-
additive tion
Warm min. 40% min. -13 °F
regions max. 45% (-25 °C)
Cold min. 50% max. -40 °F
regions max. 55% (-40 °C) >

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