engine AUDI A8 2013 Workshop Manual

202 Intellig ent technol ogy
- If you damage the fro nt spoiler, or if you
install a different spoiler, be sure the air
flow to the front brakes is not obstruct­ ed . Otherwise the brake system could
overheat reducing the effectiveness of
the ent ire brake system .
- Failure of one brake c ircuit will impair
the braking capability resulting in an in­ creased stopp ing distance. Avoid driv ing
the vehicle and have it towed to the near­ est Aud i dea ler or qualified workshop .
Brake booster
The brake booster adds extra braking power .
The brake booster works with vacuum pres­
sure which is created only when the engine is
running ¢& .
& WARNING
-Never let the vehicle ro ll to a stop w ith
the engine shut off.
- If the brake booster is not work ing, for
example when towing your vehicle, or
because the b rake booste r has somehow
been damaged, the brake pedal must be
pressed considerab ly harder to make up
for the lack of booster assistance .
Servotronic® -
advanced power
steering system
The power steering systems use the power of
the running engine to allow precise steering
with little effort.
The advanced Servotronic ® power steering
system senses the road speed and e lectroni­
cally adjusts powe r ass istance to p rov ide com ­
fortable and sa fe stee ring response exactly
matc hed to the ve hicle speed .
Power steering w il l not work if the eng ine is
off . As a result, the steering whee l w ill be hard
to turn.
The power steering fluid level is chec ked dur­
ing the scheduled ma intenance serv ices.
(D Note
If there is an e lectronic malfunction, ser­
votronic
will still function like a conven­
tiona l power steering system, providing a
constant steering support force that is no
l onger proportionate to the vehicle speed.
This is most not iceable when t urning the
steering wheel at low speeds (for example
when pa rking), - more effort w ill be re­
q uired than us ual.
- Be aware of the diffe rent than usual
steering response and adjust your steer­
ing force acco rding ly.
- Have the problem checked and set right
by an A udi dealer as soon as poss ible.
(D Tips
- When the eng ine is running, never ho ld
the stee ring wheel turned all the way to
the rig ht or to the left fo r longer than 15
seconds. The powe r stee ring pump will
overheat the hydraulic fluid i f yo u keep
holding the stee ring wheel turned all the
way. This is likely to damage the power steering system.
- If the powe r steering system sho uld fai l
entire ly, or if the engine is not runn ing
(for example, wh ile be ing towed), you
w ill still be able to stee r the veh icle.
However,
considerably more effort will
be requi red to do so.
- If the power steering system should
have a leak, or is not functioning proper­
ly, contact your author ized Audi dealer
immed iately.
- The power steer ing system req uires a
specially fo rmu lated hyd raulic fluid. The
powe r stee ring fluid reservoir is located
in the engine comp art ment¢
page 234.
T he cor rect fluid level in the reservoir is
impo rtant fo r proper functioning of the
powe r stee ring .

Driving with your
quattro ®
With All Wheel Drive, all four wheels are driv­
en .
Gene ral inform ation
W ith All Whee l Drive, power is distributed to
all four wheels . This happens automatically
depending on your driving style and the road
conditions at the t ime. See also
t::;> page 198.
W ith the spo rt differential*, power d istribu­
tion to the rear wheels is variable and can be
adj usted with Aud i drive select*
t::;> page 109.
Always read and fo llow safety precautions
c:> .&. .
Winter t ires
When driving in the winter , your vehicle with
All Wheel Dr ive has an advantage, even with
regular t ires. In winter road conditions it may
be advisable to mount winter tires (or all-sea­
son tires) for improved driveability and brak­ ing: these tires must be mounted on
a ll four
w he els .
See also c:> page 264, Winter tires.
Sn ow cha ins
Where snow cha ins a re mandatory on certa in
roads, th is normally a lso applies to vehicles
with A ll Wheel Drive
c:> page 265, Snow
chains .
Replacing whe els/ tires
Vehicles w ith All Whee l Dr ive must always
have tires of the same size. Also avoid t ires
with different tread depths. For details see
page
c:> page 260, New tires and replacing
tires and wheels .
Off-Road driving?
Your Audi does not have enough ground clear­
ance to be used as an off-road vehicle.
It is
therefore best to avoid rough tracks and un ­
even terrain as much as possible. Also refer to
c:> page207.
Int ellig ent technolog y 203
A WARNING
Always adjust your driv ing to road and traf­
fic conditions. Do not let the extra safety
afforded by All Wheel Dr ive tempt you into
taking extra risks .
- Although the All Wheel Drive is very ef­
fective, always remember that braking capacity is lim ited by tire t raction. You
should therefore not d rive at excessive
speeds on icy or slippery road surfaces.
- On wet road surfaces, be careful not to
drive too fast because the fron t wheels
could begin to slide on top of the water (aquaplaning) . If this should occur, yo u
will have no warning from a s udden in­
crease in engine speed as w ith a front­
wheel drive veh icle. Always drive at
speeds which are su ited to the road con­
ditions - risk of crash.
Energy management
Starting ability is optimized
Energy management controls the distribution
of electrical energy and thus optimizes the
availability of electrical energy for starting
the engine .
If a vehicle with a conve ntiona l energy system
is not drive n for a long per iod of t ime, the bat­
tery is discharged by idling current consume rs
(e.g . immobilizer). In certain circumstances it
can resu lt in the re being insuff icient energy
available to start the engine.
Intelligent energy management in your vehi­
cle handles the distribution of e lectrica l ener­
gy. Starting ability is marked ly improved and
the life of the battery is extended.
Basica lly, energy management consists of
b atte ry diagno sis, i dling current man age­
ment
and d y namic ene rg y management .
Battery diagno sis
Battery diagnosis continuously determines
the sta te of the battery. Sensors determine
battery voltage, battery current and battery
Ii),,
•
•

204 Intelligent technology
temperature. This determines the current
state of charge and the power of the battery .
Idling current management
Idling current management reduces energy
consumption while the vehicle is stand ing.
With the ignition switched off, it contro ls the
energy supply to the various e lectrica l compo ­
nents. Data from battery diagnosis is consid­
ered.
Depending on the battery's state of charge,
individual consumers are gradually turned off
to prevent excessive discharge of the battery
and thus maintain starting capability.
Dynamic energy management
While the vehicle is being driven, dynamic en­
e rgy management distributes the energy gen ­
erated according to the needs of the individu­
al components. It regu lates consumption, so
that more electrical energy is not being used
than is being generated and ensures an opti­
mal state of charge for the battery.
Q) Tips
- But even energy management cannot negate the limits of physics. Consider
that the power and life of a battery are
li mited.
- If starting ability is threatened, the indi­
cator light[•) appears
Q page 16, D
Battery.
What you should know
The highest priority is given to maintaining
starting capability.
The battery is severely taxed in short-distance
driving, in city traffic and during the cold time
of year. Abundant electrical energy is re­
qu ired, but only a little is generated.
It is also
cr itica l if the engine is not running and electri­
cal components are turned on. In this in­
stance energy is being consumed but none is
being generated .
It is in precise ly these situations that you will
notice energy management active ly regu lat­
ing the d istribution of energy.
Vehicle stands for an extended period
If you do not drive your vehicle over a period
of seve ral days or weeks, e lectr ica l compo­
nents are gradually cut back or switched off .
This reduces energy consumption and main­
tains starting capability over a longer period .
Some of the convenience functions may not
operate, such as the interior lights or the
power seat adjustment . The convenience
funct ions will be available again when you
switch on the ignition and start the engine.
With the engine turned off
If you listen to the radio, for example, with
the engine turned off or use other MMI func­
tions, the battery is being discharged .
If starting capab il it y is jeopardized due to en­
ergy consumption, the following warning ap­
pears in the MMI display:
Please start the engine soon or the system
will be turned off.
The warn ing ind icates that the system will be
turned off automatically after 3 minutes. If
you w ish to continue using the functions, you
have to sta rt the eng ine .
With the engine running
Although electrical energy is generated when
the vehicle is being driven, the battery can be­
come discharged. This happens mostly when
little energy is being generated and a grea t
deal consumed and the battery's state of
charge is not optimal.
T o b ring the energy bala nce back into equili­
brium, consumers which req uire espec ially
large amounts of energy are temporarily cut
back or switched off . Heating systems in par­
ticular require a great deal of energy. If you
notice, for examp le, that the heated seats* or
the heated rear window are not heating, they
have been temporarily cut back or switched .,.

off. These systems will be avai lable again as
soon as the energy ba lance has bee n restored.
You will also notice that engine idle speed has
been increased s lightly. This is normal and not
a cause for concern. By increasing engine idle
speed the additiona l energy required is gener­
ated and the battery is charged .
Intelligent technology 205
•
•

206 Driving and environment
Driving and
environment
The first 1,000 miles
(1,500 km) and
afterwards
New engine
The engine needs to be run-in during the first
1,000 miles (1,500 km).
For the fir st 600 miles (1,000
kilometers ):
.,. Do not use full throttle.
... Do not drive at engine speeds that are more
than 2/3 of the max imum permitted RPM.
... Avoid hig h engine speeds.
From 600 to 1,000 mile s (1 ,000 to
1,500 kilometers):
... Speeds can gradually be increased to the
max imum pe rm iss ible road or eng ine speed .
During and after break-in per iod
.,. Do not rev the engine up to high speeds
when it is cold. Th is app lies whether the
transm ission is i n N (Neutra l) or in gear.
After the break-in period
... Do not exceed maximum engine speed un­
der any circumstances.
.,. Upshift into the next hig her gear
before
reaching the red area at the end of the tach­
ometer scale
¢ page 10.
During the first few hours of driving, the en­
g ine's interna l friction is higher than later
when all the moving parts have been broken
in . How well this break- in p rocess is do ne de­
pends to a conside rable extent on the way the
ve hicl e is driven d uring the first 1,0 00 miles
(1, 500 k ilome ters).
0 Note
E xtremely high engi ne speeds are auto­
mat ica lly reduced. However, these rpm
lim its are progr amme d for an engine well
r u n- in, not a new engine .
{® For the sake of the environment
Do not drive with unnecessarily high en­
g ine speeds - upshifting ear ly saves fuel,
reduces no ise and protects the environ­
ment.
, New tires
If your vehicle is runni ng on new tires, drive
part icularly caref ul for the first 350 miles
(500 kilomete rs) afte r fitt ing .
_& WARNING
New tires tend to be sl ippery and mus t al­
so be "broken -in" . Be s ure to remember
this dur ing the fi rst 350 mi les (500 kilo ­
meters) . Brake gently . Avoid fo llow ing
closely behind other vehicles or other sit­
uations that m ight require sudden, hard
braking .
New brake pads
Remember that new brake pads do not have a
full bra king effect dur ing the fi rst 250 m iles
(400 kilomete rs) afte r they a re insta lled .
New brake pads have to be "broken in" before
they have optima l grab ¢.& . The break-in pe­
r iod can be conside rably longe r for vehicles
with ce ram ic brake rotors *. Yo u can co m pen­
sate for this s light ly red uced b ra ki ng power by
pushing ha rder on the br ake peda l.
During the break- in pe riod, you should avo id
putting seve re loads on the bra kes. Seve re
loads include, f or examp le, sudden ha rd b ra k­
i ng, in particular at very high speeds or, for
example, on mountain passes.
_& WARNING
N ew brake pa ds don 't have the best stop ­
p ing power and must be "broken-i n" dur­
i ng the initia l 100 to 150 miles (150 to
200 kilometers) of norma l city driving. You
ca n compe nsate for this by p ressing the
b rake pedal mo re fi rm ly. This also applies
l ater wh en new pads are i nstalled .

Catalytic converter
It is very important that your emission con­trol system (catalytic converter) is function­
ing properly to ensure that your vehicle is run­
ning in an environmentally sound manner .
.. Always use lead-free gasoline¢ page 228,
Fuel supply.
.,. Never run the tank down all the way to
empty.
.,. Never put too much motor oil in your en-
gine ¢
page 238, Adding engine oil~-
.,. Never try to push- or tow-start your veh icle.
The catalytic converter is an eff icient "clean­
up" device built into the exhaust system of
the vehicle . The catalytic converter burns
many of the pollutants in the exhaust gas be ­
fore they are released into the atmosphere.
The exclusive use of unleaded fuel is critically
importa nt for the life of the cata lytic convert­
e r and proper functioning of the engine.
A WARNING
-
- Do not park or operate the vehicle in
areas where the hot exhaust system may
come in contact with dry grass, brush,
fuel spill or other material which can cause a fire.
- Do not apply additional undercoating or
rustproofing on or near the exhaust
man ifold, exhaust pipes, catalytic con­
verter or heat shields. During driving, the
substance used for undercoating cou ld
overheat and cause a fire.
0 Note
- Be aware that just one tank filling with
leaded fuel will already seriously de­
grade the performance of the catalytic
converter.
- Do not exceed the correct engine oil level
¢ page 238.
-Do not drive until the fuel tank becomes
completely empty. The eng ine could mis­
fire . U nburned fuel could a lso get i nto
Dri vin g and en vironm ent 207
the exhaust system and this cou ld cause
the catalytic converter to overheat .
- Do not swi tch off the ignit ion while the
vehicle is mov ing.
- Do not continue to ope rate your veh icle
unde r these conditions, as othe rwise fuel
can reach the catalytic converter. This
co uld result in overheating o f the con­
verter, requir ing its replacement .
- To assure efficient operation of the Emis ­
sion Control System:
- H ave your vehicle maintained prope rly
and in accordance w ith the se rv ice rec­
ommendat ions in you r Warranty &
M aintenance boo klet.
- L ack of prope r maintenance as we ll as
improper use of the vehi cle w il l impair
the function of the em ission contro l
system and could lead to damage .
@ For the sake of the environment
Even when the Emiss ion Control System is
operat ing properly, the exha ust gas can
have a sul fur -li ke exhaust gas smell under
some operating states . This depends on
the sulfur content of the fuel being used .
Using a different brand of fue l may help,
or filling the tank with lead-free super
grade gasoline .
Avoid damaging the
vehicle
When you are drivi ng on poo r roads, or over
c ur bs, s teep ramps, etc., ma ke certai n that
low -lying parts s uch as spoilers and exhaust
system pa rts do not bottom o ut and get dam­
aged.
T h is is espec ially true for veh icles w ith low­
s lung chassis (spor ts chassis)* and fully load­
ed vehicles. •
•

208 Driving and en vir onm ent
Driving through water
on roads
Note the following to avoid vehicle damage
when driving through water, for example on
flooded roads:
- The water must not be any higher than the
bottom of the vehicle body.
- Do not drive faster than wa lking speed.
A WARNING
After driving through water, mud, slush,
etc., the brakes may be slow to take effect
because of wet brake rotors and pads. Dry
the brakes first by braking carefully to re­
sto re the full braking effect.
@) Note
- Vehicle components such as the eng ine,
transmission, suspension or electr ical
system can be severely damaged by driv­ i ng th rough water.
- Always switc h off the Start-Stop-System
when driving through water~
page 87.
(1) Tips
-Check the depth of the water before dr iv­
i ng through it.
- Do not stop the veh icle, dr ive in reverse
or switch the engine off when driving
through water .
- Keep in mind that oncoming vehicles
may create waves that raise the water
level and make it too deep for your vehi­
cle to drive th rough safely.
- Avoid dr iving through salt water because
i t can cause corrosion.
Operate your vehicle
economically and
minimize pollution
General
Your personal style of driving will determine
the economy of your vehicle, as well as ex­
haust and noise levels.
Fuel economy, environmenta l impact, and
wear on your engine, brakes and tires largely
depend on three factors:
- your personal driving style
- operating conditions
- technical limitat ions
If you ant ic ipate what you need to do next and
drive economically, you can easily cut your
fuel consumpt ion by 10-15 percent . This sec­
t ion w ill give you some tips on how you can
help the env ironment and your pocketbook.
@ Tips
The consumption estimates as published
by ENVIRONMENTAL PROTEC TION AGENCY
( E PA) and Transpo rt Canada may not corre­
spond to your actual consumption on the
road, which will vary depending upon vehi ­
cle load and speed, road and weather con ­
ditions, trip length, etc.
Drive smoothly and keep a lookout
ahead
Vehicles use the most fuel when they are ac­
celerating.
.,. Avoid unnecessary accelerating and braking.
Vehicles use the most fuel when they a re ac­
ce lerating. If you anticipate what is going to
happen next, you will need to brake less and,
t hu s, acce lerate less . Let the vehicle coast
whenever possible -for examp le when you see
that the next traff ic light is red.

Avoid full throttle
Driving at moderate speeds saves fuel and
improves your mileage.
11-Try and keep well below your car's maxi-
mum speed.
Accelerating gently reduces fuel consump­ tion, engine wear, and does not disturb the
environment.
F ue l consumption, exhaust emissions and en ­
g ine noise increase disproportionately at high
speeds. If you drive at approximately three
quarters of top speed, fuel consumption will
be reduced by one half. Never drive faster
than the posted speed limit and weather con­
d itions permit .
Reducing unnecessary idling
Even when your car is just idling it burns up
fuel.
11-Shut the engine off when you are not driv­
ing the vehicle.
"" Do not warm up the veh icle by letting the
engine run at idle .
The idling phase is automat ically reduced for
vehicles w ith the Start/Stop system . It is effi­
cient to switch
off the engine in vehicles with­
out the Start-Stop-System when stopped at ra il road crossings and long red lights. Turning
the eng ine
off for just 30 -40 seconds saves
mo re fuel than is burned by s tarting the en­
gine again.
It takes a long time fo r the engine to wa rm up
fu lly when it is running at idle. Howeve r, wear
and noxious emissions are especially high
when the engine is warming up. So you should
drive away as soon as you start the engine and
avoid running at h igh rpms while the engine is
still warming up.
CD Note
Do not leave engine idling unattended af­
ter starting. If warning lights shou ld come
on to indicate improper operation, they
Dri vin g and en vironm ent 209
would go unheeded. Extended idling a lso
produces heat, which could result in over­
heating or other damage to the veh icle or
other property.
Regular maintenance
A badly tuned engine unnecessarily wastes a lot of fuel.
11-Have your vehicle serviced at reg ular inter-
vals .
By having your ve hicle reg ularly se rviced by an
Audi dealer he lps to ensure that it runs prop­
erly and economically . The condition of your
vehicle not only affects its safety and ability to
ho ld its va lue, it also affects
fuel co nsump ­
tion .
Chec k your oil e ach t ime you fill y our t ank.
T he amou nt of o il used is re lated to engine
load and speed.
It is normal for the oil consumption of a new
engine to reac h its lowest value after a certa in
mileage has bee n driven.
You must drive your veh icle about 3,000 m iles
(5,000 kilometers) before you can properly
assess oil consumpt ion.
This also applies to fuel consumption and en­ gine output .
CD Note
-Have your veh icle ma inta ined properly
and in accordance with the service rec­
ommendations in your Warranty
& Ma in­
tenance book let . Lack of proper mainte­
nance as well as improper use of the ve­
hicle will impai r the function of the
em ission cont ro l system and cou ld lead
t o damage.
- Do not alter or remove any component of
t he Emission Control System unless ap­
proved by the manufacture r.
- Do not alter or remove any devi ce, such
as heat shie lds, switches, ign ition w ires,
valves, which are designed to protect
your vehicle's Emission Control System
•
•

210 Driving and environment
and other important vehicle compo­
nents .
Fewer short trips
Fuel consumption will always be relatively
high on short trips.
,.. Try to avo id driving short distances with a
cold engine.
The engine and catalyt ic converter have to
r each their optimal
operating temperature to
reduce fuel cons umption and noxious emis­
sions effect ively .
Just after starting, a cold engine in a mid-size
car only achieves a fuel economy of 6-8 miles
per gallon (30-40 l/100 km). After about a
half a mile, fuel economy climbs to 12 mpg
(20 l/100 km). After about
2.5 mi les (4 km),
the engine is at its proper operating tempera­
ture and fuel economy has reached a norma l
level. So you can see that you should avoid
short tr ips whenever possible.
The
outside temperature is also critical in this
regard. Your car consumes more fuel in the
winter than in the summer.

212 Trailertowing
Trail er load dis tr ibut ion
Be sure the load in the trai ler is held securely
in place to prevent it from shifting forward,
backward or sideways.
N eve r all ow a p assenger to rid e in a trailer
~.&. in Driving instructions on page 213.
Engine cooling sy stem
Towing a tra iler makes the eng ine work hard­
er . It is important that the cooling system's
performance is up to the addit ional load .
Make sure that the cooling system has eno ugh
flu id.
Tir e pressure
When tow ing a tra iler, inflate the t ires of your
vehicle to the co ld tire pressure listed under
" Full load " on the label loca ted o n the dr iver's
side B-pillar (v is ible when the door is open).
I nflate trailer tires to tra iler and tire manufac­
turers' specifications.
Lights
Check to make sure both veh icle and trailer
l ights are wor king p roperly.
Safe ty chain s
Be sure tra iler safety cha ins are properly con­
nected from the trailer to the hitch on the ve ­
h icle . Leave enough slack in the chains to per­
mit turning corners . When you install safety
cha ins, make su re they w ill not drag on the
road when yo u are driving.
The chains shou ld cross under the tra iler
tongue to prevent it from dropping in case of
separat ion from the hitch .
Adjusting the Audi drive select
Make sure the vehicle is on a level surface be­
for e
hitching up the tra iler and b efor e adjust ­
ing the tongue weight . The vehicle must be i n
auto or comfort driving mode and not raised
~ page 109, ~CD .
Make sure that the vehicle is lowered . In Info ­
tainment, select:
I CARI function button > Low­
e r
control button . If you must drive under poor road conditions,
you can raise the vehicle
afte r coupling the
trailer or
a fter adjust ing the tongue we ight
~ page 111.
(D Note
-Changes in temperature or load can af­
fect the height of the vehicle .
- Always select auto or comfort mode .
Otherw ise, the tongue load specified for
your vehicle will no longer be applicable.
Driving instructions
Driving with a trailer always requires extra
core and consideration.
T o obtain the best possible hand ling of vehicle
and trailer, please note the fo llowing:
.. Do not tow a loaded t railer when you r ca r it­
self is not loaded .
.. Be especially carefu l when passing other
vehicles.
.. Observe speed limits.
.. Do not drive at the maximum permissible
speed .
.. Always apply brakes early .
.. Monitor the temperature gauge .
Weight di stribut ion
T owing a loaded trailer with an empty car re ­
su lts in a highly unstable d istribution of
weight. If this cannot be avoided, drive at very
l ow speeds only to avoid the risk of losing
steering control.
A "balanced" rig is easier to operate and con­
trol. This means that the tow vehicle should
be loaded to the extent possible and permissi­
ble , while keep ing the trailer as light as possi­
ble under the ci rcumstances. Whenever poss i­
ble , transfer some ca rgo to the luggage com ­
partment of the tow vehicle while obse rv ing
tong ue load requi rements and vehicle load ing
considerations .
Speed
The higher the speed, the more d ifficu lt it be­
comes fo r the driver to cont rol the rig. Do not
1111>