check engine AUDI A8 2021 User Guide

4N0012721BF
Checking and Filling

Fueling procedure

RAZ-0013


Fig. 175 Right rear side of the vehicle: opening the fuel
filler door

[RAZ-1124

Fig. 176 Fuel filler door with attached fuel cap
The fuel filler door is unlocked or locked by the
central locking system.
>» Unlock the vehicle if necessary.
> Conventional drive system: Press on the left
side of the fuel filler door to open it > fig. 175.
> Plug-in hybrid drive: Pull on the EV switch in the
driver's door. The fuel filler door will open auto-
matically after venting is complete.
> Unscrew the tank cap counterclockwise.
> Place the cap from above on the open fuel filler
door > fig. 176.
> Plug-in hybrid drive: Note the information for
refueling at the end of this chapter.
> Insert the fuel pump nozzle all the way into the
fuel filler neck.
> Begin fueling. Once the fuel pump nozzle turns
off the first time, the fuel tank is full. Do not
continue fueling, or else the expansion space in
the tank will be filled with fuel.
> After the fuel pump has switched off, wait five
seconds before removing the nozzle to allow

1) Depending on the engine and country

the rest of the fuel to finish dripping into the
fuel tank.
> Turn the fuel cap clockwise until it clicks into
place.
> Close the fuel filler door and then press on the
left side until it latches.
The correct fuel type for your vehicle can be
found ona label located on the inside of the fuel
filler door. For additional information on fuel, see
=> page 269.
For the tank capacity in your vehicle, refer to the
Technical Data > page 344.
To reduce the risk of fuel leaking out or vapors
escaping, make sure that the fuel tank is closed
correctly. Otherwise the ES indicator light will
turn on.

Z\ WARNING
Improper fueling procedures and improper
handling of fuel can lead to explosions, fires,
severe burns, and other injuries.
— Do not smoke. Keep away from open flames.
— The ignition must be switched off when re-
fueling.
— Mobile devices, radio devices, and other ra-
dio equipment should always be switched
off when refueling. Electromagnetic rays
could cause sparks and start a fire.
— If you do not insert the fuel pump nozzle all
the way into the filler tube, then fuel can
leak out. Spilled fuel can ignite and start a
fire.
— Never get into the vehicle when refueling. If
there is an exceptional situation where you
must enter the vehicle, close the door and
touch a metal surface before touching the
fuel pump nozzle again. This will reduce the
risk of electrostatic discharge that can cause
flying sparks. Sparks can start a fire when
refueling.

Z\ WARNING
Audi does not recommend transporting fuel

containers inside the vehicle. Fuel could leak

271

Checking and Filling


out of the container and ignite, especially dur-
ing an accident. This can cause explosions,
fires, and injuries.
— If you must transport fuel in a fuel contain-
er, note the following:
— Always place the fuel container on the
ground before filling. Never fill the fuel
container with fuel while it is inside or on
the vehicle. Electrostatic discharge can oc-
cur while refueling and the fuel vapors
could ignite.
— When using fuel containers made of met-
al, the fuel pump nozzle must always re-
main in contact with the container to re-
duce the risk of static charge.
— Insert the fuel pump nozzle as far as pos-
sible into the filler opening while refuel-
ing.
— Follow the applicable legal regulations in
the country where you are driving when
using, storing and transporting fuel con-
tainers.
— Make sure that the fuel container meets
the industry standards, for example ANSI
or ASTM F852-86.

©) Note
— Remove fuel that has overflowed onto any
vehicle components immediately to reduce
the risk of damage to the vehicle.
— Never drive until the fuel tank is completely
empty. The irregular supply of fuel that re-
sults from that can cause engine misfires.
Uncombusted fuel may enter the exhaust
system and increase the risk of damage to
the catalytic converter.
@) For the sake of the environment
— Do not overfill the fuel tank, or fuel could
leak out when the vehicle is warming up.
— Fuel should never enter the sewer system or
come into contact with the ground.
@) Tips
The fuel filler door on your vehicle does not
lock if you lock the vehicle from the inside us-
ing
the central locking switch.
272
G) Tips
Applies to: vehicles with plug-in hybrid drive
— When inserting the fuel pump nozzle, make
sure that you do not press on the fuel filler
door opener @) with the fuel pump nozzle.
See the label in the fuel filler door @)
> fig. 176. Otherwise, a valve will close in
the fuel filler neck and fueling will stop even
if the tank is not full.
— You must vent the tank system again if you
press on the fuel filler door opener. The fuel
pump nozzle can stay in the fuel filler neck
when doing this. Vent the tank system by
pulling the EQ) switch in the driver's door
again.
— If the engine turned off because the fuel
level was too low, then you may need to re-
fuel with up to 4.0 gallons (15 liters) of fuel
in order for the vehicle to detect the new
fuel level. Otherwise, the engine may not
restart.
— Fuel can age and may lead to problems
when starting. Audi recommends replacing
the fuel in your vehicle within six months.

4N0012721BF
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


Opening and closing the hood
The hood is released from inside the vehicle.



RAZ-0016|


Fig. 180 Unlocked hood: lever
Make sure the wiper arms are not raised up from
the windshield. Otherwise the paint could be
damaged.
Opening the hood
> Applies to: vehicles with plug-in hybrid drive:
Switch the ignition off before releasing the
hood so that the gasoline engine does not start
automatically.
> With the door open, pull the lever <> below
the instrument panel in the direction of the ar-
row > fig. 179.


D_ The & symbol is not available in all countries.
276
>» Raise the hood slightly > page 274.
> Press the lever > fig. 180 in the direction of the
arrow. This releases the hooks.
> Open the hood.
Closing the hood
> Push the hood down until you override the
force of the strut.
> Let the hood fall lightly into the latch. Do not
press it in. > /\.
Messages
B Warning! Hood is not locked. Stop vehicle
and check the lock
The hood latch is not locked correctly. Stop im-
mediately and close the hood.

Z\ WARNING
— 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.
— For safety reasons, the hood must always be
latched securely while driving. Because of
this, always check the hood after closing it
to make sure it is latched correctly. The hood
is latched if the front corners cannot be lift-
ed.
— If you notice that the hood is not latched
while you are driving, stop immediately and
close it, because driving when the hood is
not latched increases the risk of an accident.

4N0012721BF
Checking and Filling


Engine compartment overview
The most important check points.



Fig. 181 Typical location of the reservoir and the engine oil filler opening (example)
Observe the safety precautions > page 274, Gen-
eral information.
@ Washer fluid reservoir (>) > page 287
@ Jump start point (+) under a cover, (-) with
hex head screw > page 286, Charging the 12
Volt vehicle battery > page 323, Jump start-
ing
Engine oil filler opening (7) > page 279
Brake fluid reservoir (OC) under a cover
=> page 283
Coolant expansion tank for combustion en-
gine (£) > page 282
© Plug-in hybrid drive: coolant expansion tank
for the high-voltage system (-) > page 282
©
©®&
@ Sticker* for engine oil specifications
=> page 277
The engine oil filler opening may be located ina
different area depending on the specific engine.
@ Tips
Plug-in hybrid drive*: read the information re-
garding the coolant expansion tank under
= page 282 and the jump start under >@ in
Preparation on page 324.
Engine oil
If the engine oil level is too low
If you need to add engine oil, use an oil that is
listed on the sticker. The sticker is located at the
front
of the engine compartment > page 277,
fig. 181. When using the engine oil listed on the
sticker, you can adjust the oil level as often as
needed.
If engine oil that meets the recommended speci-
fication is not available, in an emergency you
may add a maximum of 1 quart (1 liter) of
ACEA C3 or API SN engine oil one time until the
next oil change.
277

>

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.

4N0012721BF
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&#39;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. >