fuel pressure AUDI S4 2021 Owners Manual

8W1012721BC
Driving


do not inadvertently press the accelerator
pedal and always shift into “P” when the ve-
hicle is stopped.
— If you leave the vehicle, switch the ignition
off and take the key with you. This is espe-
cially important when leaving persons or an-
imals in the vehicle. Otherwise, the vehicle
could start unintentionally, the parking
brake could release, or electronic equipment
could activate, which increases the risk of an
accident.
— No persons or animals should be left in a
locked vehicle. Locked doors make it more
difficult for emergency workers to enter the
vehicle, which puts lives at risk.
— If you do not begin driving immediately af-
ter releasing the brake pedal, your vehicle
may begin to roll backward. Press the brake
pedal
or set the parking brake immediately.
@) Note
If you have to stop on an incline, always press
the brake pedal to hold the vehicle in place to
reduce the risk of the vehicle rolling back-
ward. Do not try to hold the vehicle in place
by pressing and holding the accelerator pedal.
The transmission can overheat, which increas-
es the risk of damage.
Hill hold assist
If you take your foot off of the brake pedal when
driving on hills, the braking force will be held for
several seconds. At that time, you can start driv-
ing without the vehicle rolling backward.

Requirement: the driver's door must be closed,
the engine must be on, and the vehicle must be
traveling uphill.
> To activate hill hold assist, press and hold the
brake pedal for several seconds while the vehi-
cle is stationary.

ZA WARNING
— If you do not begin driving immediately af-
ter releasing the brake pedal, your vehicle
may begin to roll backward. Press the brake

pedal or set the parking brake immediately.

— The hill hold assist cannot hold the vehicle
on inclines in every scenario (for example,
on slippery or icy ground).
Gears and driving programs
(y—
(2—*


RAZ-0410:




R
N
i
D/S
~~ NEI
Fig. 94 Center console: selector lever


The automatic transmission shifts automatically
depending on the selected gear and the current
driving style. When driving with a moderate driv-
ing style, upshifting early and downshifting late
will help to improve fuel economy. When driving
with a sporty driving style, the transmission per-
mits higher RPMs.
The gears are displayed next to the selector lever.
— P (Park)
—R (Reverse): driving in reverse
—N (Neutral): idle
—D (Drive)
Selecting a gear
Requirement: the ignition must be switched on.
— Bring the vehicle to a full stop and press the
brake pedal.
— Press the release button () on the selector lev-
er.
—To select the nearest gear, move the selector
lever forward or back until you feel the first
pressure point.
—To skip a gear (for example, move from “D” to
“R”), move the selector lever past the pressure
point in the desired direction.
—The label next to the selector lever for the se-
lected gear will light up.
97

Driving

ient and environmentally-friendly

9g
Your driving style greatly influences the amount
of fuel and energy consumed, the environmental
impact, and the wear on the engine, brakes, and
tires. Note the following information for efficient
and environmentally-conscious driving:
— Turn off electrical equipment that is not need-
ed, for example seat heating*.
— Anticipate upcoming traffic situations while
driving to avoid unnecessary acceleration and
braking.
— Avoid driving at high speeds.
— Avoid adding extra weight to the vehicle if pos-
sible, for example by not leaving roof racks or
bike racks installed when they are not needed.
— Make sure the tire pressure is correct.
— Have maintenance performed regularly on the
vehicle.
— Do not let the engine run while the vehicle
parked.
— Do not drive with winter tires during the summ-
er.
— Use the Start/Stop system.
— Utilize the engine braking effect.
— Avoid driving short distances when possible.
@® Tips
The amount of noise produced by the vehicle
can increase significantly when driving with a
sporty style. Show respect to others around
you and the environment with the way you op-
erate your vehicle, especially at night.
ME ey
Your vehicle is equipped with an intelligent ener-
gy management system for distributing electrici-
ty. This significantly improves the starting ability
and increases the vehicle battery life.
@) Tips
— If you drive short distances frequently, the
vehicle battery may not charge enough
while driving. As a result, convenience func-
tions for electrical equipment may be tem-
porarily unavailable.
102
— The vehicle battery will gradually drain if
the vehicle is not driven for long periods of
time, or if electrical equipment is used
when the engine is not running. To ensure
that the vehicle can still be started, the
electrical equipment will be limited or
switched off.
I Cr Te (1
B Drive system: malfunction! Safely stop vehi-
cle
There is a malfunction in the drive system. The
brake
booster and the power steering may stop
working. Stop the vehicle immediately or as soon
as possible and do not continue driving. Secure
the vehicle against rolling before exiting the vehi-
cle > page 96. Have the problem corrected by an
authorized Audi dealer or authorized Audi Service
Facility.
B Drive system: malfunction! Please contact
Service
There is a malfunction in the drive system. Drive
slowly to an authorized Audi dealer or authorized
Audi Service Facility to have the malfunction cor-
rected.
Start/Stop system
Applies to: vehicles with Start/Stop system
The Start/Stop system can help increase fuel
economy and reduce CO2 emissions.
In Start/Stop mode, the engine shuts off auto-
matically when stopped, for example at a traffic
light. If certain conditions are met, the engine
may stop before the vehicle has come to a com-
plete stop. If you press the accelerator pedal
when this happens, the engine will start and driv-
ing power will be transmitted.
The ignition and important assist systems such
as the brake booster will remain available during
the Stop phase. The engine will restart automati-
cally when needed.
The Start/Stop system is automatically activated
once the ignition is switched on.

8W1012721BC
Checking and Filling

The indicator light can also turn on if the fuel fill-
er cap is not closed correctly > page 218),
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
[2 time!

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



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

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

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.
— 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.


1) Depending on the engine and country
221

Checking and Filling

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 223,
fig. 159. 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.
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.
G) Tips
Audi recommends using engine oils provided
by Audi Genuine Parts.
Messages
Hiturn off engine. Oil pressure too low
Stop driving and switch the engine off. Check the
engine oil level > page 225.
— If the engine oil level is too low, add engine oil
=> page 225. 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.
Applies to: vehicles with oil level warning
2 Please add oil immediately.
Stop driving and switch the engine off. Check the
engine oil level > page 225 and add engine oil
immediately > page 225.
3 Add max. x qt (x l) oil. You can continue
driving
224
Add the amount of oil shown immediately
=> page 225.
EA 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.
3 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.
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.
G) Tips
The oil pressure warning =} is not an oil level
indicator. Always check the oil level regularly.

Wheels

Glossary of tire and loading
terminology
Accessory weight
means the combined weight (in
excess of those standard items
which may be replaced) of auto-
matic transmission, power steer-
ing, power brakes, power win-
dows, power seats, radio, and
heater, to the extent that these
items are available as factory-in-
stalled equipment (whether in-
stalled or not).
Aspect ratio
means the ratio of the height to
the width of the tire in percent.
Numbers of 55 or lower indicate a
low sidewall for improved steer-
ing response and better overall
handling on dry pavement.
Bead
means the part of the tire that is
made of steel wires, wrapped or
reinforced by ply cords and that is
shaped to fit the rim.
Bead separation
means a breakdown of the bond
between components in the bead.
238
Cord
means the strands forming the
plies in the tire.
Cold tire inflation pressure
means the tire pressure recom-
mended by the vehicle manufac-
turer for a tire of a designated
size that has not been driven for
more than a couple of miles (kilo-
meters) at low speeds in the three
hour period before the tire pres-
sure is measured or adjusted.
Curb weight
means the weight of a motor ve-
hicle with standard equipment in-
cluding the maximum capacity of
fuel, oil, and coolant, air condi-
tioning and additional weight of
optional equipment.
Extra load tire
means a tire designed to operate
at higher loads and at higher in-
flation pressures than the corre-
sponding standard tire. Extra load
tires may be identified as “XL”,
“xl”, “EXTRA LOAD”, or “RF” on
the sidewall.

Wheels

B-pillar (driver's side) > fig. 167,
> fig. 168. The location may vary
depending on the model.
Use the tire pressure specified for
a normal vehicle load when the
vehicle is partially loaded > table
on page 247. If driving the vehi-
cle when fully loaded, you must
increase the tire pressure to the
maximum specified pressure > A.
Checking and correcting tire
pressure
>Check the tire pressure at least
once per month and also check it
before every long drive.
> Always check the tire pressure
when the tires are cold. Do not
reduce the pressure if it increas-
es when the tires are warm.
>Refer to the sticker > fig. 168
for the correct tire pressure.
>Correct the tire pressure if nec-
essary.
>Save the changed tire pressure
> page 254.
> Check the pressure in the spare
tire (compact spare tire)*. Al-
ways maintain the maximum
temperature that is specified for
the tire.
246


Z\ WARNING
Always adapt the tire pressure
to your driving style and the ve-
hicle load.
—Overloading can lead to loss of
vehicle control and increase
the risk of an accident. Read
and follow the important safe-
ty precautions in > page 248.
—The tire must flex more if the
tire pressure is too low or if
the vehicle speed or load are
too high. This heats the tire up
too much. This increases the
risk of an accident because it
can cause the tire to burst and
result in loss of vehicle con-
trol.
—Incorrect tire pressure increas-
es tire wear and has a negative
effect on driving and braking
behavior, which increases the
risk of an accident.

@) Note
Replace lost valve caps to re-
duce the risk of damage to the
tire valves.
(*) For the sake of the envi-
ronment
Tire pressure that is too low in-
creases fuel consumption.

Wheels

be five 150 lbs. passengers in
your vehicle, the amount of
available cargo and luggage
load capacity is 650 lbs.
(1400-750 (5 x 150) = 650
lbs.)
5. Determine the combined
weight of luggage and cargo
being loaded on the vehicle.
That weight may not safely ex-
ceed the available cargo and
luggage load capacity calculat-
ed in Step 4.
6. If your vehicle will be towing a
trailer, load from your trailer
will be transferred to your vehi-
cle. Consult this manual to de-
termine how this reduces the
available cargo and luggage
load capacity of your vehicle.
>Check the tire sidewall
(=> page 236, fig. 165) to deter-
mine the designated load rating
for a specific tire.
Wheel bolts and rims
Wheel bolts
Wheel bolts must be clean and loosen/tighten
easily.
Rims
Rims with a bolted rim ring* or with bolted wheel
covers* consist of multiple pieces. These compo-
nents were bolted together using special bolts
and a special procedure. You must not repair or
disassemble them > A\.
250

ZA WARNING
Wheel bolts that are tightened or repaired in-
correctly can become loose and result in loss
of vehicle control, which increases the risk of
an accident. For the correct tightening specifi-
cation, see > page 266, Finishing.
— Always keep the wheel bolts and the threads
in the wheel hub clean and free of grease.
— Only use wheel bolts that fit the rim.
— Always have damaged rims repaired by an
authorized Audi dealer or authorized Audi
Service Facility. Never repair or disassemble
rims yourself, because this increases the risk
of an accident.
Winter tires significantly improve the vehicle's
handling when driving in winter conditions. Be-
cause of their construction (width, compound,
tread pattern), summer tires provide less traction
on ice and snow.

> Use winter tires on all four wheels.
> Only use winter tires that are approved for your
vehicle.
> Please note that the maximum permitted
speed may be lower with winter tires > A\ in
General information on page 235. An author-
ized Audi dealer or authorized Audi Service Fa-
cility can inform you about the maximum per-
mitted speed for your tires.
> Check the tire pressure after installing wheels
=> page 245.
The effectiveness of winter tires is reduced great-
ly when the tread is worn down to a depth of
0.16 in (4 mm). The characteristics of winter tires
also decrease greatly as the tire ages, regardless
of the remaining tread.
@) For the sake of the environment
Reinstall summer tires at the appropriate
time, because they provide better handling
when roads are free of snow and ice. Summer
tires cause less road noise, tire wear, and fuel
consumption.

Wheels

under controlled conditions on a specified gov-
ernment test course.
For example, a tire graded 150 would wear one
and one half (1 1/2) times as well on the govern-
ment course as a tire graded 100.
The relative performance of tires depends upon
the actual conditions of their use, however, and
may depart significantly from the norm due to
variations in driving habits, service practices and
differences in road characteristics and climate.
Traction
The traction grades, from highest to lowest, are
AA, A, Band C. Those grades represent the tire's
ability to stop on wet pavement as measured un-
der controlled conditions on specified govern-
ment test surfaces of asphalt and concrete. A tire
marked C may have poor traction performance
oA.
Temperature
The temperature grades are A (the highest), B,
and C, representing the tire's resistance to the
generation of heat and its ability to dissipate
heat when tested under controlled conditions on
a specified indoor laboratory test wheel.
Sustained high temperature can cause the mate-
rial of the tire to degenerate and reduce tire life,
and excessive temperature can lead to sudden
tire failure > A.
The grade C corresponds to a level of perform-
ance which all passenger car tires must meet un-
der the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels
of performance on the laboratory test wheel than
the minimum required by law.

Z\ WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor-
nering, hydroplaning or peak traction charac-
teristics.

252

AN WARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, or excessive loading, either separately or
in combination, can cause heat buildup and
possible tire failure.

ZA\ WARNING
Temperature grades apply to tires that are
properly inflated and not over or underinflat-
ed.

Tire pressure monitoring
system
(1) General notes
Each tire, including the spare (if provided),
should be checked monthly when cold and inflat-
ed to the inflation pressure recommended by the
vehicle manufacturer on the vehicle placard or
tire inflation pressure label. (If your vehicle has
tires of a different size than the size indicated on
the vehicle placard or tire inflation pressure la-
bel, you should determine the proper tire infla-
tion pressure for those tires).
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system
(TPMS)
that illuminates a low tire pressure tell-
tale when one or more of your tires is significant-
ly under-inflated. Accordingly, when the low tire
pressure telltale illuminates, you should stop and
check your tires as soon as possible, and inflate
them to the proper pressure. Driving on a signifi-
cantly under-inflated tire causes the tire to over-
heat and can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread life,
and may affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver's re-
sponsibility to maintain correct tire pressure,
even if under-inflation has not reached the level
to trigger illumination of the TPMS low tire pres-
sure telltale.

8W1012721BC
Fuses and bulbs

@) Note
If a new fuse burns out again shortly after you
have installed it, have the electrical system
checked as soon as possible by an authorized
Audi dealer or authorized Audi Service Facili-
t y.
G@) Tips
— The following table does not list fuse loca-
tions that are not used.
— Some of the equipment listed in the follow-
ing tables applies only to certain model ver-
sions or certain optional equipment.

Fig. 184 Driver's footwell (left-hand drive vehicle): fuse
panel with plastic clip
3
=f
= & a

x
Ss $ 2 8

Fig. 185 Front passenger's footwell (right-hand drive vehi-
cle): fuse panel with plastic clip


f ) (brown)
No. | Equipment

1 | Catalytic converter heating

2 | Engine components

Exhaust doors, fuel injectors, radiator in-
let, crankcase housing heating

Vacuum pump, hot water pump, NOx sen-
4 |sor, particulate sensor, biodiesel sensor,
exhaust doors

Brake light sensor

6 | Engine valves, camshaft adjustment

Heated oxygen sensors, mass airflow sen-
sor, water pump

Water pump, high pressure pump, high
8 |pressure regulator valve, temperature
valve, engine mount

Hot water pump, motor relay, 48 V drive-
train generator, 48 V water pump

10 | Oil pressure sensor, oil temperature sensor

Clutch position sensor, 48 V drivetrain
11 |generator, water pump, 12 V drivetrain
generator

12 | Engine valves, engine mount


13 | Engine cooling

273

Fuses and bulbs






Fuse panel @) (brown) Fuse panel (© (black)
14 | Fuel injectors, engine control module 11 Left rear door control module, left rear
15 |Ignition coils, heated oxygen sensors power window
16 | Fuel pump 12 | Parking heater
Fuse panel (®) (red) Fuse panel (0) (black)
No. | Equipment No. | Equipment

Anti-theft alarm system

Front seat electronic, seat ventilation,
rearview mirror, rear climate control sys-

































tem control panel, windshield heating, di-
agnostic connection
2 Diagnostic interface, vehicle electrical sys-
tem control module
3 |Sound generator
4 |Clutch position sensor
5S |Engine start, emergency shut-off
6 Diagnostic connection, traffic information
antenna (TMC)
7 |USB input
8 |Garage door opener
9 Audi adaptive cruise control, distance reg-
ulation
11 | Front camera
12 | Right headlight
13 | Left headlight
14 | Transmission fluid cooling
Fuse panel (©) (red)
No. | Equipment
1 {Ignition coils
2 |Climate control system compressor
S |Left headlight
6 |Automatic transmission
7 |Instrument panel
8 | Climate control system blower
9 |Right headlight
10 | Dynamic steering
11 | Engine start



2 | Engine control module
3 Left front seat electronics, lumbar sup-
port, massaging seat
4 | Automatic transmission selector lever
5 |Horn
6 |Parking brake
7 | Diagnostic interface
8 | Roof electronics control module
9 |Emergency call module
10 | Airbag control module
11 Electronic Stabilization Control (ESC), An-
ti-Lock Braking System (ABS)
12 | Diagnostic connection, light/rain sensor
13 | Climate control system
14 | Right front door control module
15 | Climate control system compressor
16 | Brake system pressure reservoir
Fuse panel (©) (black)
No. | Equipment
Front seat heating
2 |Windshield wipers
Left headlight electronics
4 Panoramic glass roof / sliding/tilting sun-
roof
5 |Left front door control module
6 | Sockets
7 Right rear door control module, right rear
power window
All wheel drive control module
9 | Right headlight electronics
10 Windshield washer system/headlight

washer system control module

274