Coolant Losses; Adding Coolant; Overheating - Audi 100 Quattro Owner's Manual

VEHICLE CARE

Coolant losses

Coolant losses may indicate a leak in the
cooling system. In this case, the cooling
system should be inspected immediately
by your authorized Audi dealer. It is not
sufficient merely to add coolant.
In a sealed system, losses can only
occur if the boiling point of the coolant is
exceeded as a result of overheating.
Overheating can occur if:
§
the flow of air to the radiator is
obstructed by leaves, dust, insects or by
additional lights installed in front of the
radiator grille;
§
the boiling point of the coolant
been reduced due to an incorrect mixture
of coolant and water – see previous
page;
§
the radiator fan is not working – see
"Radiator fan", or;
§
the vehicle is being driven up a
hill in a low gear with engine speed very
high and at very high
temperature-see "Radiator fan".
114
If the cause for the overheating cannot
be determined and corrected, contact
your authorized Audi dealer immediately,
otherwise serious engine damage co
result.

Adding coolant

Turn off the engine and allow it to cool
down.
WARNING
Reduce the risk of scalding from hot
coolant by following these steps.
§
If the coolant reservoir cap must
has
be removed wait until the engine has
cooled down. The cooling system is
under pressure.
§
Protect lace, hands and arms by
covering the cap with a large, thick
rag to protect against escaping fluid
long
and steam.
§
Carefully and slowly turn cap one
ambient
turn to allow excess pressure to esca-
pe before completely removing cap.
Always add antifreeze and water in the
ratio specified on the container by the
antifreeze manufacturer.
uld
Increasing the
coolant to more than 60 % is not only
uneconomical, it is also detrimental to
engine cooling.
Only use quality phosphate-free anti-
freeze containing ethylene glycol. Such
antifreeze is available at your Audi
dealer.
Antifreeze, other than specified by Audi,
may cause corrosion of the cooling
system, leading to engine overheating
and damage.
Only for topping-up coolant, a small
amount of antifreeze containing ethylene
glycol and phosphates may be used, if
recommended antifreeze is not available.
Cold antifreeze and cold water should
only be added when the engine is cold,
too.
§
After adding coolant, run the engine
at idle speed for a few seconds.
§
Check coolant level once again. Add
more coolant if necessary.
Always heed WARNINGS on page 102.
antifreeze in the