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
q ui res little atte ntion .
The 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 ma nufactur
er's glycol-based coolant additive G13 an tifreeze
with ant icor rosion additives
(50% for USA mod
e ls;
60% fo r Canadia n models). This m ix tu re
bo th ass ures the necessa ry fros t prote ction and
protects metal componen ts in the engi ne's coo l
ing system from corrosion and scaling .
It also
raises the boiling point of the coolant.
D o not red uce the con cen trat ion of the coolant in
the summer by adding p lain wa ter.
The propor
tion of coolant additive mu st be at least 50 %
but not more than 60%
to maintain 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, antifreeze is added at the
factory for temperatures down to:
- -3 1 °F ( -3 5 °C) USA
- -4 0 °F ( - 40 °C) Canada.
If yo u m ust add coo lant, use a m ixt ure of water
and coolant addit ive. Mixing the cool ant additive
with d istilled w ater is recommended .
_& WARNING
Before you che ck anythi ng in t he eng ine com
pa rtment, a lways read and heed a ll WARN
INGS
~ .& in Working in the engine compart
ment on page 203 .
(D Note
-Before winter se ts in, have the coo lant
checked to see if the coolant additive in your
vehicle is sufficient to meet the c limate con -
Checking and Filling
ditions. This is especia lly important if you
live in a region whe re the winter is extreme
ly cold. If necessary, increase the propo rtion
of coolant addit ive to
60%.
- Whe n adding coolant additive to your cool
ing system, remember :
- We recommend us ing o nly coola nt addi
tive G 12++ or G13 (c hec k the label) for
y o ur vehi cle. Thi s coo lant ad ditive is av ail
abl e at a uth orized Au di dea le rs. Ot her
types o f ant ifreeze ca n sign ifican tly re
d uce corrosion protection. The resu lting
cor ros ion can cause a loss of coolant and
se rious 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 could result in damage not cov
ered by your New Veh icle Limited War ra nty .
Checking the engine coolant level
The engine coolant level can be checked with a
quick glance .
Fig. 186 E ngine compar tmen t: cover on t he coo lant expan
s io n t ank
Befo re you check anything in the engine compart
me nt,
always read and heed all WARNINGS
~ .&. in Working in the engine compartment on
page 203.
" Park your veh icle on a leve l s u rface.
" Sw itch off the ig nit ion .
.. Read the eng ine coolant leve l from the coo lant
expansion tan k
r=;,fig. 186, r=;,page 205,
fig . 183.
W ith a cold eng ine, the coolant level ..,.
209
Checking and Filling
should be between the "min " and "max" mark
ings. When 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 205.
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.
A 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 itto 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 .
210
(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 203 .
.. Requirement: There must be a residual amount
of coolant in the expansion tank
i:::>Q) .
.. Turn off the engine .
.. Let the engine cool down .
.. Place a thick rag over the coolant expansion
tank <::>
page 209, fig. 186 and carefully twist
the cap counter-clockwise
c::> &,.
.. Add coolant mixed in the correct ratio
<::> page 209, 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 209, 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.
~