228  Check ing  and  filling 
cold  engine,  the  coo lant  level should  be  be 
tween  the  "min"  and  "max"  markings.  When 
the  engine  is warm,  the  level may  be s light ly 
above  the  "max"  marking. 
The location  of  the  coolant  expansion  tank 
can  be  seen  in the  engine  compartment  illus
tration 
r:::;, page 222. 
To obtain  an  accurate  reading,  the  engine 
must  be  switched 
off. 
The expansion  tank  in you r vehicle  is equipped 
with  an  e lectric  coolant  level sensor. 
When  the  coolant  level  is too  low, the  warning  light  in the  Auto-Check System 
r:::;, page  16 will 
i l lum ina te unti l you  add  coolant  and  the  level 
has  been  restored  to  normal.  Even though 
there  is an  electric  coolant  level  senso r, we 
still  recommend  you  check the  coolant  leve l 
from  time  to  time. 
Coolant  los s 
Coolant loss  may  indicate  a leak in the  cool ing 
system.  In  the  event  of coolant  loss,  the  cool 
ing system  should  be  inspected  immediately 
by your  authorized  Audi dealer.  It  is not 
enough  merely  to  add  coolant. 
I n a 
sea led system,  losses  can occur  only  if 
the  boiling  point  of  the  coolant  is exceeded  as 
a result  of  overheat ing. 
A WARNING 
The cooling  system  is under  pressure  and 
can  get  very  hot.  Reduce the  risk of scald
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 covering  the 
cap with  a  large,  thick  rag. 
- Turn the  cap slowly and  very carefully  in 
a counter-clockwise  direction  wh ile ap
plying  light,  downward  pressure  on  the 
top  of the  cap. 
- To avoid be ing  burned,  do  not  spill ant i
freeze  or  coolant  on the  exhaust  system 
' 
or  hot  engine  parts.  Under  certain  cond i
tions,  the  ethylene  glycol in engine  coo l
ant  can catch  fire. 
(D Note 
Do not  add  any type  of  radiator  leak  sea l
ant  to  your vehicle's  engine  coolant.  Add i ng  radiator  repa ir fl uid 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 
War ranty. 
Adding  coolant 
Be very careful  when  adding  engine  coolant. 
Before you  check anyth ing  in the  eng ine  com
partment, 
always  read  and  heed  all  W ARN
INGS c:> A in  Working  in  the  engine  compart
ment  on page 
220 . 
.. Turn off the  engine. 
..  Let  the  engine  cool  down. 
..  Place a thick  rag  over the  coolant  expansion 
tank 
<:;> page 227, fig . 174 and carefully 
twist  the  cap  co unte r-clockwise c:> .&, . 
.,. Add coolant  . 
.,.  Twist  the  cap on  aga in 
tightly. 
Replacement  engine  coo lant  must  conform  to 
exact  spec ificat ions 
r:::;, page 22 7, Coolant. 
E ven  in an  emerge ncy, if coolant  add i-
t ive G12 ++, G 12+  or  G12  is not  available,  do 
not use  a d iffe rent  additive.  Use plain  water 
instead  unti l you can  get  the  correct  additive 
and  can  restore  the  correct  ratio . This shou ld 
be  done  as  soon  as  possible. 
If you  have  lost  a considerab le amount  o f 
coolant,  then  you  sho uld add  cold  antifreeze 
and  co ld water  on ly w hen the  engine  is cold. 
Always  use 
new engine  coo la nt  when  refilling. 
Do not  fill coola nt  above  the  "MAX" mark . Ex
cess  coola nt  will be fo rced  out  through  the 
pressure  relief  valve  in the  cap w hen  the  e n-
gine  becomes  hot.  .,.