2021 AUDI A7 check engine

4K8012721BF
Trailer towing

Trailer towing
Driving with a trailer
eT e e eeu)
Your vehicle is primarily intended for transport-
ing people and luggage. However, if you drive
with a trailer, follow the technical requirements,
the operation and driving tips, and the legal reg-
ulations.
Driving with a trailer affects the vehicle's energy
usage, performance, and wear. It also requires
higher concentration from the driver.

Z\ WARNING
Do not transport any people in a trailer due to
the risk of fatal injury.
Technical requirements
Trailer hitch

Only use a trailer hitch with a removable ball
hitch mount and ball hitch. The trailer hitch must
be permitted for the vehicle, the trailer and the
permitted total weight of the trailer being
pulled. Above all, it must be securely and safely
attached to the vehicle trailer.
Never mount a trailer hitch on the bumper. The
trailer hitch must be mounted in a way that does
not impair the function of the bumper. Do not
make any changes to the exhaust system and the
brake system.
Check regularly if the trailer hitch is securely
mounted. Always follow the instructions given by
the trailer hitch manufacturer.
Trailer brakes
If the trailer has its own brake system, then fol-
low the manufacturer specifications. However,
the brake system on the trailer must never be
connected to the vehicle brake system.
Engine cooling system
Driving with a trailer means a higher load on the
engine and the cooling system. The cooling sys-
tem must be designed for additional load and
contain enough coolant > @®.
CG) Note
Longer inclines cannot be driven without a
suitable cooling system, especially if the out-
side temperatures are high. Otherwise, this
increases the risk of engine damage.
Operating instructions
Towing capacity
Your vehicle can only be operated with class 1 or
class 2 trailers.
Load distribution
Poor cargo load and distribution can negatively
impact vehicle handling. Load the trailer based
on the following criteria as much as possible:
— Store objects in the vehicle luggage compart-
ment, if possible. The vehicle should always
carry the heaviest possible load and the trailer
should have the lightest possible load.
— Distribute the load in the trailer so that the
heavy objects are as close to the axle as possi-
ble.
— Secure objects so that they do not slide.
— Utilize the maximum permitted tongue weight
if possible.
Tires
Set the tire pressure on your vehicle for a “full
load”; see the tire pressure sticker > page 284. If
necessary, also adjust the tire pressure on the
trailer according to the manufacturer's specifica-
tions.
The trailer and the vehicle should be equipped
with winter tires when driving in winter tempera-
tures.
Outside mirrors
If you cannot see the traffic behind the trailer
with the standard exterior mirrors, then you
must attach additional exterior mirrors. Adjust
them so you have a sufficient visibility behind
you.
Exterior lighting
Follow the legal regulations for lighting on your
trailer that are applicable in the country where
135
>

Checking and Filling

Checking and Filling
Fuel
Types of gasoline
The correct gasoline grade is stated on the inside
of the fuel filler door.
The vehicle is equipped with a catalytic converter
and must only be driven with unleaded gasoline.
Audi recommends using TOP TIER Detergent Gas-
oline. For additional information on TOP TIER De-
tergent Gasoline, visit www.toptiergas.com.
The individual gasoline grades are differentiated
by octane ratings. This value is given with (R
+M)/2 equating to AKI or in RON.
The headings below match the sticker in the fuel
filler door (examples):
UNLEADED FUEL ONLY MIN. (R+M)/2 87
Regular / MIN. RON 91 Regular
Use regular gasoline with minimum 87 AKI /
91 RON > ©.
Audi recommends using premium gasoline with
minimum 91 AKI / 95 RON to achieve the rated
horsepower and torque.
UNLEADED FUEL ONLY PREMIUM MIN. (R
+M)/2 91 / SUPER MIN. RON 95
Using premium gasoline with minimum 91 AKI /
95 RON is recommended.
If premium gasoline is not available, you can also
use regular gasoline 87 AKI / 91 RON. However
this does reduce the engine power slightly.
UNLEADED FUEL ONLY PREMIUM MIN. (R
+M)/2 93 / SUPER PLUS MIN. RON 98
Using premium plus gasoline with at least 93
AKI / 98 RON is recommended.
If no premium plus gasoline is available, you can
also use premium gasoline with 91 AKI / 95 RON.
However this does reduce the engine power
slightly.
254
@) Note
— Filling the tank just one time with leaded
fuel or other metallic additives will cause
permanent deterioration to the catalytic
converter function.
— When gasoline with an octane rating that is
too low is used, high speeds or heavy engine
load can lead to engine damage.
@® tips
The vehicle may be filled with fuel that has a
higher octane rating than what is required by
the engine.
Gasoline mixture
Gasoline with alcohol or MTBE (Methyl-Tert-
Butyl-Ether)
You can use unleaded gasoline mixed with alco-
hol or MTBE (generally labeled as oxygenated
compounds) as long as the fuel meets the follow-
ing conditions:
Gasoline with methanol content (methyl alco-
hol or methanol)
— Anti-Knock Index is at least 87 AKI
—No more than 3% methanol
— More than 2% solvent
Gasoline with ethanol content (ethyl alcohol or
ethanol)
— Anti-Knock Index is at least 87 AKI
—No more than 15% ethanol
Gasoline with MTBE content
— Anti-Knock Index is at least 87 AKI
—No more than 15% MTBE
Gasoline adapted to the season
Many gasoline fuels are adapted to the seasons.
When the season changes, refueling at high-traf-
fic gas stations is recommended. It is more likely
that the gasoline will be suitable for the season
there.
@) Note
— Gasoline with methanol content that does
not meet the specified conditions may cause >

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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.
Refueling
Messages
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 258.
A 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
& 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 119.
Al Fuel filler door open. Please press button
again to refuel
Fueling is possible for a little while after pressing
the ) button. You must press the M) button
again if the time limit is exceeded.
255

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Checking and Filling



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.
@ Tips
Your vehicle is equipped with a misfueling
guard. It allows the vehicle to be fueled only
with
the correct fuel pump nozzle.
—Aworn or damaged nozzle or a nozzle that
is too small may not be able to open the die-
sel misfueling guard. If this is the case, try
turning the nozzle before inserting it in the
fuel filler neck, use a different fuel pump, or
see an authorized Audi dealer or authorized
Audi Service Facility for assistance.
—The misfueling guard does not open when
adding fuel from a fuel container. When re-
fueling with a reserve canister, you must use
the funnel stored in the luggage compart-
ment > page 257.
@) 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. 158. 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 EN) 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.

Fig. 159 Fuel tank filler neck with the mounted funnel
257

>

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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 259, 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
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.
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 radiator fan can switch on at any
time!

High voltage! Switch off the engine be-
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
cause fatal injuries. Touching a damaged
high-voltage component can result ina
fatal electric shock.

The catalytic converter can be damaged
"271 if the oil level is too high!
oy
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.

Always follow the instructions in the op-
erating manual.



259

Checking and Filling


— 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 262, fig. 164. 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.
— 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.


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


260
() 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 >

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Checking and Filling

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



RAZ-0016|

Fig. 163 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.

2) The &> symbol is not available in all countries.
> With the door open, pull the lever 2 below
the instrument panel in the direction of the ar-
row > fig. 162.
>» Raise the hood slightly > page 259.
> Press the lever > fig. 163 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. > JX.
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.

ZX 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.


261

Checking and Filling


Engine compartment overview
The most important check points.


RAZ-1051


Fig. 164 Typical location of the reservoir and the engine oil filler opening (example)
Observe the safety precautions > page 259, Gen-
eral information.
© @
®©®©
© @
Washer fluid reservoir (>) 9 page 272
Jump start point (+) under a cover, (-) with
hex head screw > page 272, Charging the 12
Volt vehicle battery > page 311, Jump start-
ing
Engine oil filler opening (S27) > page 264
Version 1: coolant expansion tank for com-
bustion engine (=f) under a cover
=> page 267
Brake fluid reservoir (OC) under a cover
=> page 269
Version 2: coolant expansion tank for com-
bustion engine (-£) > page 267
Plug-in hybrid drive: coolant expansion tank
for the high-voltage system ( page 267
Sticker* for engine oil specifications
=> page 262
262
The coolant expansion tank and the engine oil
filling opening may be located in different places
within the engine compartment, depending on
the engine version.
Gi) Tips
Plug-in hybrid drive*: read the information re-
garding the coolant expansion tank under
= page 267 and the jump start under >@ in
Preparation on page 312.
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 262,
fig. 164. When using the engine oil listed on the
sticker, you can adjust the oil level as often as
needed.