Engine cooling system
Coolant
The engine coolant performs two functions: it
keeps the engine from overheating and it pro
te cts the engine from freezing in the winter .
The cooling system is sealed and generally re
qu ires little attention .
The cooling system has been filled at the fac
tory with a permanent coolant which does not need to be changed. The coolant consists of a
mixture of water and the manufacturer's gly
col-based coolan t additive G12++ ant ifreeze
with a nticorrosion add itives (50% fo r USA
models; 60% for Canad ian models). This mix
ture bot h assu res the ne ces sary frost protec
tion and protects metal components in the
engine's cooling system from corrosion and
scaling. It also raises the bo ili ng po int of t he
coolant.
D o not red uce the concentration of the coo l
ant in the summe r by adding plain water .
The
proportion of coolant addit ive must be at
least 50% but not mo re than 60 %
to main
tain antifree ze protection and cooling efficien
cy. If the coolant frost protect ion is too low,
the coolant could freeze and damage the veh i
cle heating and eng ine cooling system .
For year-round driving, antifree ze is added at
the factory for temperatures down to:
- -3 1°F (-35°C)USA
- -4 0 ° F ( - 4 0 °C) Canada.
You can mix t he G12 ++ cool ant ad ditive with
o ther addit ives (G1 2+ or G1 2). Alway s check
w ith your author ized Audi dealer.
& WARNING
Before yo u check any thing in the engine
compartment, always read and hee d all
W AR NIN GS
Q .&. in Working in the engine
compartment on page 222.
(D Note
- Before win ter se ts in , have the coolan t
checked to see if the coolant addit ive i n
Checkin g and fillin g 229
your vehicle is sufficient to meet the cli
mate conditions . This is especia lly impor
tant if you live in a reg ion where t he win
ter is extreme ly co ld. If necessary, in
crease t he p ropo rtion of coo lant add itive
t o 60% .
- Whe n add ing coolant additive to your
cooling system , remember :
- W e re co mme nd usin g only cool ant ad
dit ive G 12++ (check t he labe l) for your
vehi cle. This coolan t addi tive is ava ila
b le at a uthorized Audi dea le rs . Othe r
types of ant ifreeze can significant ly re
d uce co rrosi on protection. The res ult
i n g corrosion can ca use a loss of co ol
ant and ser io us eng ine damage .
- Do not add any type of rad iator leak seal
ant to you r vehicle's eng ine c oolant .
Add ing radiator repair fl uid may adverse
ly affect t he f unction and performance of
yo ur cooling sys tem and co uld resu lt i n
damage not covered by yo ur New Ve hicle
Li mi ted Warran ty.
Checking the engine coolant level
The engine coolant level can be chec ked with
a quick glan ce.
:!, MAX
% MIN
Fig. 180 En gin e compar tment: mark ings on t he coo l
a n t expa nsion tank
Befo re you check a nyth ing in the eng ine com
partment,
always read and heed all WARN
INGS ¢.&, in Working in the engine compart
men t on page
222 .
"' Switch off the ignition .
"' Read the engine coo lant level from the coo l
ant expa nsion tank
Qfig . 180. Wit h a co ld
eng ine , the coo lant level s hou ld be between
1JJ>-
230 Check ing and filling
th e "min" and "max" markings. When the
engine is wa rm, the level may be slightly
above the "max" marking.
The location of the coolant expansion tank
can be seen in the engine compartment ill us
tration ¢
page 224 .
To obtain an accurate read ing , the engine
must be switched
off .
The expans io n tank in you r vehicle is equipped
with an e lectric coolant level se nsor.
When the coolant level is too low, the warning light in the A uto-Check System ¢
page 15 will
i llum inate u nti l 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 leve l
from time to time.
Coolant loss
Coolant loss may indicate a leak in the cooling
system. In the event of coolan t loss, the cool
ing system should be inspected immedia tely
by your authorized Audi dealer. It is not
enough mere ly to add coolant.
I n a
se aled system, losses can occur only if
the boiling point of the coolant is exceeded as
a result of overheat ing.
A WARNING
T he cooling system is unde r pressure and
can get ve ry hot . Reduce the risk of sca ld
ing from hot coolant by following these
steps.
- Turn off the engine and allow it to cool
down.
- Protect yo ur face, hands and arms from
escaping fluid and steam by cove ring the
cap with a large, thick rag.
- Turn the cap slowly and very carefu lly in
a counter-clockwise direction wh ile ap
plying light, downward pressure on the
top of the cap .
- To avoid being b urned, do not spill ant i
freeze or coolant on the exhaust system or hot eng ine parts . Under ce rtai n condi -
'
tions, the ethylene glycol in engine coo l
ant can catch fire.
@ Note
Do not add any type o f radiato r leak sea l
ant to your vehicle's engine coolant. Add
i ng radiator repa ir fluid may adverse ly af
fect the funct ion and performance of your
cooling system and could result in damage not covered by your New Veh icle L imited
Warranty .
Adding coolant
Be very careful when adding engine coolant.
Before you check anyth ing in the engine com
partment,
always read and heed all WARN
INGS
c> .&. in Working in the engine compart
ment on page
222 .
• Turnoff the engine .
• Let the eng ine cool down.
• Place a thick rag over the coolant expansion
tank
c> page 22 9, fig . 180 and carefully
tw ist t he cap co unter-clockwise c> ,& .
• Add coo lant .
• Twist the cap o n again
tightly.
Replacement engine coo lant must conform to
exact spec ificat ions ¢
page 229, Coolant .
Even in a n emerge ncy, if coo la nt addi-
t ive G 12++ , G12+ or G12 is not ava ilable , do
not use a d iffe ren t addit ive. Use plain water
instead unt il you can get the cor rect add itive
and can restore the correct ratio . This sho uld
be don e as soon as possible.
If you have los t a consider able amount o f
coolant, then you sho uld add cold ant ifreeze
and cold wate r on ly when the engine is cold.
Always use
new engine coo lant when refilling.
Do not f ill coolant above the "MAX" mark. Ex
cess coola nt w ill be fo rced o ut through the
pressure relief valve in t he cap when the e n-
gine becomes ho t.
Ill>
