2016 AUDI S8 engine overheat

Trailer mod e
conditions are unfavorable - particularly when
going downhill.
Red uce veh icle speed
imm ediatel y if the tra ile r
shows the s lightest sign of swaying.
Do not try
to stop the sway in g b y accele rating .
Observe speed lim its . In some areas, speeds for
ve hicl es towing tra ilers are lower than for reg ula r
veh icles.
A lways apply brakes early . When dr iving down­
h ill , sh ift into a lower gear to use the engine
b raking effect to slow the veh icle. Use of the
brakes a lone can cause them to overheat and fail.
Air suspension*
When driving with a tra iler, activate the trailer
mode of the air suspension . Switch the air sus­
pens ion tra iler mode on when you a re towing a
tra ile r. This will limit the regulat ion by the air
suspens ion while driving . Select in the MM I:
ICARI function button > (Car )* sys tem s control
button >
Vehicle setting s > Air su sp .: to wi ng >
On .
Coolant temperature
The coolan t temperature gauge¢ page 10 must
be observed carefully. The coo lant temperature
can increase if you drive on long inclines in a low
gear at high engine speeds. Reduce your speed
immed iate ly if the LEDs in the top part of the dis­
p lay turn on.
For more information about indicator lights, re­
fer to.
¢page 15.
A WARNING
Anyone not properly restrained in a moving
vehicle is at a much greater risk in an acci­
dent. Never let anyone ride in your car who is
not properly wearing the restraints provided
by Audi.
Trailer mode notes
Important to know
Your vehicle hand les different ly when towing a
trai ler because of the additiona l weight and dif­
ferent weight distr ibut ion. Safety, performance
204
-
and economy will g reatly depend on how carefu l­
l y you load your trai ler and operate your rig .
Befo re yo u actually tow yo ur t railer, pract ice
turning, stopping and backing up in an area away
from traffic. Keep practicing unti l you have be ­
come complete ly familiar with the way your vehi­
cle-tra iler combination behaves and responds .
Backing up is diff icult and requ ires practice.
Backing up with a trailer genera lly req uires steer ­
ing action opposite to that when backing up your
vehicle witho ut a trailer .
Maintain a greater distance between yo ur vehicle
and the one in front of you. You will need more
room to stop . To compensate for the trailer, you
will need a larger than normal turning radius .
When passing, remember tha t you canno t accel­
erate as fast as you normally wou ld because of
the added load . Make sure you have enough room
to pass. After passing, allow p lenty of room for
your trailer before changing lanes again.
Avoid jerky starts, sharp turns or rapid lane changes.
(D Tips
- Do not tow a trailer du ring the break-i n pe ri­
od of your vehicle.
- If you tow a tr aile r, your A udi may requi re
more frequent ma intenance due to the ex­
tra load ¢
page 281.
Parking on a slope
Do not park on a slope with a trailer . If it cannot
be avoided, do so only after doing the following:
When parking:
.,. App ly the foot brake.
.,. Have someone p lace chocks unde r both the ve­
hicle and the trailer wheels .
.,. With chocks in place, slowly release the brakes
until the wheel chocks abso rb the load .
.,. Turn the whee ls towards the curb.
.,. App ly the parking brake .
.,. Select the P selector lever posit ion.

Cooling system
Coolant
The engine coolant performs two functions: it
keeps the engine from overheating and it pro ­
tects the engine from freezing in the winter .
The cooling system is sealed and generally re­
quires little attention.
T he cooling system has been filled at the factory
with a permanent coolant which does not need to
be changed . The coolant consists of a mixture of
specially condit ioned water and the manufactur ­
er's glycol-based coolant additive Gl3 antifreeze
with anticorrosion additives (SO% for USA mod­
e ls; 60% for Canadian mode ls). This m ixture
both ass ures the necessa ry frost protection and
protects metal components in the engine's coo l­
ing system from corrosion and scaling .
It also
raises the boiling point of the coolant.
Do not red uce the concent ration of the coolant in
the summer by adding p lain water.
The propor­
tion of coolant addit ive mu st be at least 50 %
but not more than 60 %
to mainta in antifreeze
protection and cooling efficiency. If the coolant
frost protection is too low, the coolant could
freeze and damage the vehicle heating and en­
g ine cooling system .
For year-round driving, antifree ze is added at the
factory for temperatures down to :
- -31° F(- 3S°C)USA
- - 40 ° F ( - 40 °C) Canada.
If you must add coolant, use a m ixture of water
and coolant addit ive. M ixing the coolant additive
with d istilled water is recommended .
_& WARNING
Before you check anythi ng i n t he engine com­
partment, always read and heed all WARN ­
INGS
¢ .&. in Working in the engine compart­
ment on page 220 .
(D Note
-Befo re winter se ts in, have the coo lant
checked to see if the coolant additive in your
vehicle is sufficient to meet the cl imate con -
Check ing and Filling
ditions. This is especially important if you
live in a region where the winter is extreme­
ly cold. If necessary, increase the proportion
of coolant additive to 60%.
- When adding coolant additive to your cool­
ing system, remember :
- We recommend us ing only coolant add i­
tive Gl2+ + or Gl3 for yo ur vehicle. This
coolant addit ive is avai lab le at aut horized
A udi dealers . O ther types of antifree ze can
significantly reduce corrosion pro tect ion .
The resulting corrosion can cause a loss of
coolant and serious engine damage.
- Do not add any type of radiator leak sealant
to your vehicle's engine coolant. Adding ra ­
diator repair fluid may adversely affect the
function and performance of your cooling system and cou ld resu lt in damage not cov­
ered by your New Veh icle Limited Warra nty .
Checking the engine coolant level
The engine coolant level can be checked with a
quick glance.
Fi g. 2 01 Engin e compar tmen t: cover o n th e coo lant expan ­
sion t ank
Before you check anything in the engine compart­
ment,
always read and heed all WARNINGS
¢ A in Working in the engine compartment on
page 220 .
Park your vehicle on a level surface .
.,. Switch off the ignition .
.,. Read the engine coolant level from the coo lant
expansion tank
¢ fig . 201, ¢page 222. With a
cold engine, the coolant level should be be-
tween the "min" and "max" markings. When .,.
227

Checking and Filling
the engine is warm, the level may be slightly above the "max" marking.
The location of the coolant expansion tank can be
seen in the engine compartment illustration
¢ page 222.
To obtain an accurate reading, the engine must
be switched off.
The expansion tank in your vehicle is equipped
with an electric coolant level sensor.
When the coolant level is too low, the warning
light in the Auto-Check System¢
page 15 will il­
luminate until you add coolant and the level has
been restored to normal. Even though there is an
electric coolant level sensor, we still recommend
you check the coolant level from time to time .
Coolant loss
Coolant loss may indicate a leak in the cooling
system . In the event of coolant loss, the cooling
system should be inspected immediately by your
authorized Audi dealer.
It is not enough merely
to add coolant.
In a
sealed system, losses can occur only if the
boiling point of the coolant is exceeded as a re­
sult of overheating.
_& WARNING
The cooling system is under pressure and can
get very hot. Reduce the risk of scalding from
hot coolant by following these steps.
- Turn off the engine and allow it to cool
down.
- Protect your face, hands and arms from es­
caping fluid and steam by covering the cap
with a large, thick rag.
- Turn the cap slowly and very carefully in a
counter-clockwise direction while applying
light, downward pressure on the top of the
cap.
- To avoid being burned, do not spill anti­
freeze or coolant on the exhaust system or
hot engine parts. Under certain conditions,
the ethylene glycol in engine coolant can
catch fire.
228
(D Note
Do not add any type of radiator leak sealant
to your vehicle's engine coolant. Adding radia­
tor repair fluid may adversely affect the func­
tion and performance of your cooling system
and could result in damage not covered by
your New Vehicle Limited Warranty .
Adding coolant
Be very careful when adding engine coolant.
Before you check anything in the engine compart­
ment,
always read and heed all WARNINGS
¢.& in Working in the engine compartment on
page 220 .
.. Requirement: There must be a residual amount
of coolant in the expansion tank ¢(D .
.. Turn off the engine .
.. Let the engine cool down .
.. Place a thick rag over the coolant expansion
tank ¢
page 22 7, fig. 201 and carefully twist
the cap counter-clockwise ¢&, .
.,. Add coolant mixed in the correct ratio
r::!> page 22 7, Coolant up to the MAX marking.
.. Make sure that the fluid level remains stable.
Add more coolant if necessary .
.. Twist the cap on again
tightly.
Replacement engine coolant must conform to ex­
act specifications ¢
page 22 7, Coolant.
We recommend using only coolant additive G12+
+, G13 or in an emergency G12+ . Do
not use a
different additive. In an emergency use plain wa­
ter until you can get the correct additive and can
restore the correct ratio. This should be done as
soon as possible.
If you have lost a considerable amount of cool­
ant, then you should add cold antifreeze and cold
water only when the engine is cold.
Always use
new engine coolant when refilling.
Do not fill coolant above the "MAX" mark . Excess
coolant will be forced out through the pressure
relief valve in the cap when the engine becomes
hot.
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