engine AUDI S6 2014 Workshop Manual

196 Intelligent technology
@ Tips
-ABS and ASR on ly work correctly when
all four wheels are equipped with identi­
ca l tires. Different tire sizes can lead to a
reduct ion in engine power.
- You may hear noises when the systems
described are working.
Switching on and off
- If the indicator light DJ or til] (USA
mode ls)/ [I] (Canada models) appears,
there may be a malfunction
¢ page 20 ,
¢ page 19.
ESC turns on automatically when you start the engine.
Fig. 178 Ce nter co ns ole, f). O FF bu tton
ESC levels
Sport mode on
The following situations are exceptions where
it may be usefu l to switch on sport mode to
allow the wheels to spin:
- Rocking the vehicle to free it when it i s st uck
- Dr iving in deep snow or on loose g round
- Driving with snow chains
Sport mode off
Beha vio r
The ESC a nd ASR stabilization fun ct ions The fu ll stabilization function o f the ESC
are limited ¢.&, .
Op eration Pr ess the 1.$ O FFI button .
Indicato r I) turns on.
lights
Driv er mes- Stabiliza tion control (ESC ): Sport
sage s Warning! R educed stability
,8. WARNING
You should only switch sport mode on if
your driving abilities and road cond itions
permit.
- The stabilization function is limited
when sport mode is sw itched on. The
dr iv ing whee ls could spin and the vehicle
cou ld swe rve, especially on slick or slip­
pery road surfaces .
{D) Tips
Sport mode cannot be switched on when
adapt ive cr uise control* is switched on.
-
and ASR is availab le again .
Press the
1 .$ O FF I button again.
fl tu rns off.
Stabilization c ontrol (ESC ): On
Braking
General information
What affects braking efficiency?
Operating conditions and driving habits
The bra kes on today's automobiles a re still
s u bje ct to wear, depending largely on ope rat­
i ng conditions and driving hab its
¢ A . On
vehicles that are either driven most ly in stop­
and-go city traff ic or are driven hard, the
brake pads should be checked by your author­
ized Audi dealer more often than specified in
the
Warranty & Maintenance booklet . Failure .,,_

to have your brake pads inspected can result
in reduced brake performance.
On steep slopes, you should use the brak ing
effect of the engine. This way, yo u prevent un­
necessary wea r on the brake system . If you
must use your brakes, do not hold the brakes
down continuously. Pump the brakes at inter ­
vals.
Moi stu re or r oad salt
Under certain conditions, for examp le, when
driving through water or very heavy rain, or
even after washing your vehicle , the braking
effect can be reduced due to moisture (or in
free zing conditions ice) on the brake pads. A
f ew care ful brake applications should dry off
the brake pads or remove any ice coatings.
When you a re d riving at higher speeds with
the w indshield wipers on, the brake pads will
briefly touch the brake d iscs in regular inter­
vals so as to improve reaction t ime when brak­
ing on wet surfaces . You the driver will not no­
tice anything .
The effectiveness of the brakes can be reduced
when the vehicle is dr iven on a salt -covered
road and the brakes are not used . Here too ,
you should clean off accumu lated salt coat ing
from brake discs and pads with a few carefu l
appl ications o f the brake ¢,&. .
Cor ro sion
There may be a tendency for dirt to build up
on the brake pads and corrosion to form on
the discs if the car is not dr iven regularly or
on ly for short trips with l ittle use of the
brakes .
If the brakes are not used frequently , or if cor­
rosion has fo rmed on the discs, it is advisable
to clean off the pads and discs by brak ing
firm ly a few times from a moderately h igh
speed ¢.&. .
F a ults in the brake system
If you should notice a
sudden increase in
b rake pedal travel, then one of the two bra ke
circu its may have failed¢,&. .
Int ellig ent technolog y 197
Low br ake fluid lev el
Malfunctions can occu r in the brake system if
the b rake fluid level is too low. The brake fluid
level is monitored electronica lly.
Brake booster
T he brake booster wo rks with vacuum pres­
s ur e which is created only when the engine is
runn ing ¢.&. .
Brake lining we ar statu s
Brake lining wear may be checked by visual in­
spect ion of the condition of the brake pads
th rough the open ings in the wheel. If neces­
sary, the wheel may be removed for th is in­
spection ¢
page 263, Changing a wheel.
A WARNING
-=
-You should perform braking maneuvers
for the purpose of cleaning the brake
system only if road conditions permit.
Other road users must not be put at risk -
you may cause an accident!
- Before descend ing a steep grade, reduce
speed and sh ift transmission into a lower
gear or lower dr iving range. Do not ride
the brakes or hold the pedal down too
long or too often . Th is could cause the
brakes to get hot and diminish braking
efficiency.
- Do not "ride the brakes" by rest ing your
foot on the pedal when you do not intend
to b rake. This may cause the brakes to
overheat, premature wear and increased
stopping distance.
- Unde r ce rtain cl imatic and operat ing
conditions such as passing thro ugh wa ­
ter, driving in heavy rain or after washing
the vehicle, the effectiveness of the brakes can be reduced . In winter, ice can
accumulate on the brake pads, lin ings,
discs and drums . Carefully app ly brakes
for a test . Brakes will dry and ice coat­
ings w ill be cleaned off after a few care­
fu l brake applicat ions.
- Driving for an extended period of time on
salt-covered roads without using your brakes can a lso affect bra king efficiency. ..,.
•
•

198 Intelligent technology
Clean off accumulated salt coating from
brake discs and pads with a few caref ul
brake applications.
- If you damage the front spoiler, or if you
install a different spoiler, be sure the air
flow to the front brakes is not obstruct­ ed . Otherwise the brake system could
overheat reducing the effectiveness of
the ent ire brake system.
- Failure of one brake c ircuit will impair
the braking capability resulting in an in­ creased stopp ing distan ce. Avoid driv ing
the vehicle a nd have it towed to t he near­
est Aud i dea ler o r qualified workshop.
- Never let the vehicle rol l to a stop w ith
the engine shu t off.
- If the brake booster is not working, the
brake pedal must be pressed conside ra­
bly harder to make up for the lac k of
booster assistance.
Electro-mechanical
power assist
The electro-mechanical power assist helps
the driver when steering.
Power steering adapts electronically based on
the vehicle speed.
Ind icator light s and m essages
• Steerin g defecti ve! Stop the vehicle
If th is indicator light turns on and stays on
and this message appears, t he power steering
may have fa iled.
Do
not cont inue driving . See you r autho rized
Aud i dealer or other qualified repa ir facility
fo r assistance.
l~ ij Ste ering: Sy stem malfunction ! You m ay
cont inue dri ving
If the indicator light turns on and the mes­
sage appears, the steer ing may be more diffi­
cult to move or more sens itive than usual.
Drive s low ly to your authorized Audi dealer or
qua lified workshop to have the malfunction
corrected.
(D Tips
If the . or
£'I' ij indicator light on ly stays
on for a short t ime, yo u may continue dr iv­
i ng.
Driving with your
quattro
App lies to vehicles: wit h all-w hee l drive
With a/I-wheel drive, all four wheels ore driv­
en.
General information
With all Wheel Drive, power is distributed to all four wheels. This happens automatically
depend ing on your driving style and the road
condit ions at the time. See also ¢
page 194.
With the sport diffe rent ia l*, power distribu­
t ion to the rear wheels is variable and can be
adjusted with Audi drive select*¢
page 100.
Always read and follow safety precautions
¢ &.
Winter tires
When dr iving in the win ter, yo ur vehicle wi th
all-wheel drive has an advantage, eve n with
regular tires. In winter road conditions it may
be advisable to mount winter tires (or all-sea­
son tires) for improved driveability and brak­
ing : these tires must be mounted on
all fou r
w heel s.
See also¢ page 255, Winter tires .
Tire chain s
Where tire chains are mandatory on certain roads, this norma lly also app lies to ve hicles
with all-wheel drive¢
page 256, Snow
chains .
Replacing wheel s/tire s
Vehicles with a ll-wheel drive must always
have tires of the same size. A lso avoid tires
with different tread depths . For detai ls see
page ¢
page 251, New tires and replacing
tires and wheels.
Off -Road dr iving?
Your Audi does not have enough gro und clea r-
ance to be used as an off-road vehicle .
It is jll,,

therefore best to avoid rough tracks and un ­
even terrain as much as possible . Also refer to
<=:> page 203.
A WARNING
Always adjust your driving to road and traf­
fic conditions. Do not let the extra safety
afforded by all-wheel dr ive tempt you into
taking extra risks.
- Although the all-wheel dr ive is very ef­
fective, a lways remember that braking
capacity is limited by t ire traction . Yo u
should therefore not dr ive at excessive
speeds on icy or slippery road su rfaces.
- On wet road su rfaces, be careful not to
dr ive too fast because t he fro nt wheels
c ou ld beg in to s lide on top of the wa ter
(aq uaplaning). If this sho uld occ ur, you
will have no warning from a sudden in ­
crease in engine speed as with a front ­
wheel drive vehicle. A lways drive at
speeds wh ich are suited to the road con­
ditions -risk of crash.
Energy management
Starting ability is optimized
Energy management controls the distribution
of electrical energy and thus optimi zes the
availability of electrical energy for starting the engine .
If a veh icle wit h a conventional energy system
i s not d riven for a lo ng pe riod o f time, the bat­
tery is discha rged by idling cu rrent co nsu mers
(e .g. immobilizer) . In ce rtain c ircumstances it
can result in there being insufficient ene rgy
avai lab le to start the engine .
I n tell igen t energy m anagemen t in your veh i­
cle hand les the d istribu tion of electrical ener­
gy . Starting ab ility is marked ly imp roved and
the life of the battery is extended.
B asically , energy management consists o f
battery diagnos is , idling current manage­
ment
and dynamic ene rgy man agement.
Int ellig ent technolog y 199
Battery diagnosis
Battery diagnosis continuously de termines
the state of the battery . Sensors de termine
batte ry voltage, battery current and battery
temperature . This determines the current
state of charge and the power of the battery.
Idling current management
Idling curren t management reduces energy
consumption while the vehi cle is standing.
With the ignition switched off, it controls the
energy supply to the various electrica l compo­
nents. Data from battery diagnos is is cons id­
ered .
Depending on the battery's state of charge,
i ndivid ua l cons umers are g radually turned off
to prevent excessive discharge of the battery
and thus maintain starting capability .
Dynamic energy management
While the vehicle is being driven, dynamic en ­
ergy ma nagement distrib utes the energy ge n­
erated accord ing to the needs of the individ u­
al components . It regulates consum ption, so
that more electrical energy is not being used
than is being generated and ensures an opti­
mal state of cha rge for the battery .
(D Tips
-But even ene rgy management cannot
negate the limits of physics. Consider
t hat the powe r and life of a battery are
limited .
- If start ing ability is threatened , the indi­
cator light (•) appears
c::> page 17 .
What you should know
The highest priority is given to maintaining
starting capability.
The battery is severely taxed in short-distance
driv ing, in city traff ic and during the cold time
of year . Abundant electrical energy is re -
quired, but on ly a little is generated . It is also ..,. •
•

200 Intelligent technology
critical if the engine is not running and electri­
cal components are turned on. In this in­
stance energy is being consumed but none is
being generated.
It is in precisely these situations that you wi ll
notice energy management actively regulat­
ing the distribut ion of energy .
Vehicle stands for an extended period
If you do not drive your vehicle over a pe riod
of severa l days or weeks, electrical compo­
nents are gradually cut back or switched off.
This reduces energy consumption and main­
tains starting capab ility over a longer period.
Some of the conven ience functions may not
operate, such as the inter ior lights or the
power seat adjustment. The conven ience
functions will be available again when you
switch on the ignition and start the engine.
With the engine turned off
If you listen to the radio, for example, with
the eng ine turned off or use other MMI func­
tions, the battery is being discharged .
If starting capability is jeopardized due to en­
ergy consumption, the following warning ap­
pears in the MMI display:
Please start the engine soon or the system
will be turned off.
The warning indicates that the system will be
turned off automatically after 3 minutes. If
you wish to continue using the functions, you
have to start the engine.
With the engine running
Although elect rical energy is generated when
the vehicle is being driven, the battery can be­
come discharged. This happens most ly when
little energy is being generated and a great
dea l consumed and the battery 's state of
charge is not optimal.
To bring the energy balance back into equili­
brium, consumers which require especia lly
large amounts of energy are temporarily cut
back or switched off. Heating systems in par­
ticular requ ire a great deal of energy. If you notice,
for example, that the heated seats* or
the heated rear window are not heating, they
have been temporarily cut back or switched
off. These systems will be available again as
soon as the energy balance has been restored.
You will also notice that engine id le speed has
been increased slightly. Th is is normal and not
a cause for concern. By increasing engine idle
speed the additional energy required is gener­
ated and the battery is charged.

Driving and
environment
The first 1
1000
miles
(11500 km) and
afterwards
New engine
The engine needs to be run-in during the first
1,000 miles (1 ,500 km) .
For the first 600 mile s (1,000
kilometers ):
.,. Do not use full throttle.
.,. Do not drive at engine speeds that are more
than 2/3 of the max imum permitted RPM .
.. Avoid high engine speeds .
From 600 to 1,000 mile s (1 ,000 to
1,500 kilometers):
.. Speeds can gradually be increased to the
maximum pe rm iss ib le road or eng ine speed .
During and after break-in per iod
.,. Do not rev the engine up to high speeds
when it is cold. This applies whether the
transmission is i n N (Neutra l) or in gear.
After the break- in peri od
.. Do not exceed maximum engine speed un­
der any circumstances.
.,. Upshift into the next higher gear
before
reaching the red area at the end of the tach­
ometer scale
¢ page 11.
During the first few hours of driving, the en­
g ine's interna l friction is higher than later
when all the moving parts have been broken
i n. How well this break-in p rocess is done de­
pends to a considerable extent on the way the
ve hicl e is driven du ring the first 1,000 miles
(1,500 ki lome ters).
(D Note
Extremely h igh engine speeds are auto­
mat ica lly reduced. However, t hese rpm
lim its are progr amme d for an eng ine well
r u n- in, not a new engine .
Driving and environment 201
@) For the sake of the environment
Do not drive with unnecessarily high en­
g ine speeds -upshifting ear ly saves f uel,
reduces noise and protects the environ­
ment.
New tires
If your vehicle is running on new tires, drive
particularly caref ul for the first 350 miles
(500 kilomete rs) afte r fitt ing.
.&, WARNING
N ew tires tend to be sl ippery and mus t al­
so be "b roken -in" . Be sure to remember
this dur ing the f irst 350 m iles (500 kilo­
meters) . Brake gently . Avoid fo llowing
closely behind other vehicles or other sit­
uations that m ight require sudden, hard
b raking .
New brake pads
Remember that new brake pads do not have a
full brak ing effect dur ing the first 250 m iles
(400 ki lomete rs) afte r they are installed.
New brake pads have to be "burnished in" be­
fore they have optima l grab¢ .&. .
D uring the brea k-in period, yo u should avo id
putting severe loads on the brakes. Severe
l oads include , for example, sudden hard brak­
i ng, in particular at very h igh speeds or, for
example, on mounta in passes .
.&, WARNING
New b rake pads don't have the best stop­
p ing power and must be "broken-i n" dur­
ing the initi al 100 to 150 miles (150 to
2 00 kilometers) o f no rma l ci ty driving . You
can compensate for this by pressing the b rake peda l more fi rm ly . This also applies
later when new pads are installed.
•
•

202 Driving and en vir onm ent
Catalytic converter
Appl ies to vehicles: with gasoline e ngin e
It is very important that your emission con­
trol system (catalytic converter) is function­
ing properly to ensure that your vehicle is run­
ning in an environmentally sound manner .
.. Always use lead-free gasoline¢ page 215,
Fuel supply .
.. Never run the tank down all the way to emp-
ty .
.. Never put too much motor oil in your engine
¢ page 229, Adding engine oil .. Never try to push- or tow-start your veh icle.
The catalytic converter is an eff ic ient "clean­
up" device built into the exhaust system of
the vehicle. The catalyti c converter burns
many of the pollutants in the exhaust gas be­
fore they are released into the atmosphere.
The exclus ive use of unleaded fuel is cr itically
important for the l ife of the cata lytic convert­
e r and proper functioning of the engine.
A WARNING
T he temperature of the exhaust system is
high, both when driving and after stopping
the engine .
- Never touch the exhaust tail pipes once
they have become hot. This could result
in burns.
- Do not park or operate the vehicle in
areas where the hot exhaust system may
come in contact with dry grass, brush,
fuel spill or other material which can
cause a fire.
- Do not apply additional undercoating or
rustproofing on or near the exhaust
man ifold, exhaust p ipes, catalytic con­
verter or heat shields . During driving, the
substance used for undercoating cou ld
overheat and cause a fire.
@) Note
- Be aware that just one tank f illing with
leaded fuel will al ready seriously de­
grade the perfo rmance of the cata lytic
conve rter. -
Do not exceed the correct engine oil level
¢page 229.
-Do not drive until the fue l tank becomes
completely empty . The engine co uld m is­
fire . Unburned fuel could also get into
the exhaust system and this cou ld cause
the catalytic converter to overheat.
- Do not switch off the ignition while the
vehicle is mov ing .
- Do not continue to ope rate your vehicle
under these conditions, as otherwise fuel
can reach the catalyt ic converter. Th is
cou ld result in overheating of the con­
verter, requir ing its replacement .
- To assure efficient operation of the Emis­
sion Control System:
- Have you r vehicle maintained p roperly
and in accordance w ith the service rec­
ommendations in your Warranty & Maintenance book let.
- Lack of prope r maintenance as we ll as
improper use of the vehicle wi ll impair
the function of the em ission contro l
system and could lead to damage.
@) For the sa ke of the en vironment
Even when the Emission Control System is
ope rat ing properly, the exhaust gas can
have a sulfur-like exhaust gas smell under
some operat ing states. This depends on
the sulfur content of the fuel being used .
Usi ng a different brand of fuel may help,
or f illing the tank with lead-free super
grade gasoline.
Diesel particulate filter
Applies to vehicles: with diese l eng ine
The diesel part icu late filter filters nearly all of
the soot pa rticles out of the exhaust . T he fil­
te r cleans itself automat ica lly unde r no rma l
dr iv ing cond itions . If the filte r cannot clean it­
self (for example, because you are on ly driving
short distances), the filter becomes clogged
with soot and the
II symbol for the diesel
particulate filter ill uminates ¢
page 22. ..,.

204 Driving and en vir onm ent
The consumption estimates as published
by ENVIRONMENTAL PROTECTION AGENCY
(EPA) and Transport Canada may not corre­
spond to your actual consumption on the
road, which will vary depending upon vehi ­
cle load and speed, road and weather con­
ditions, tr ip length, etc .
Drive smoothly and keep a lookout
ahead
Vehicles use the most fuel when they are ac­
celerating.
• Avoid unnecessary accelerating and braking.
Vehicles use the mo st fuel when they are ac­
celerating . If you anticipate what is go ing to
happen next, you will need to brake less and,
thus , accelerate less. Let the vehicle coast
wheneve r poss ible -for example when you see
that the next traffic l ight is red.
Avoid full throttle
Driving at moderate speeds saves fuel and
improves your mileage.
• Try and keep well below your car 's max imum
speed .
Accelerating gently reduces fuel consump­
tion, engine wear, and does not disturb the
environment .
Fuel consumption, exhaust emissions and en­
g ine no ise increase d isproportionately at high
speeds. If you dr ive at approximately three
quarters of top speed, fue l consumption will
be reduced by one half. Neve r dr ive faste r
than the posted speed limit and wea ther con­
d itions permit.
Reducing unnecessary idling
Even when your car is just idling it burns up
fuel.
• Shut the engine off when you are not dr iv ing
the vehicle. •
Do not warm up the vehicle by letting the
engine run at id le .
T he id ling phase is automatically red uced for
vehicles with the Start/Stop system . It is effi ­
cient to switch off the engine in vehicles with ­
out the Start-Stop -System when stopp ed at
railroad crossings and long red lights. Tu rning
the engine off for jus t 30-40 seconds saves
more fuel than is burned by starting the en-
. . gme again .
It takes a long time for the eng ine to warm up
fully when i t is running at idle. However, wear
and noxiou s emissions are espec ially high
when the eng ine is warm ing up . So you should
drive away as soon as you start the engine and
avo id running at high rpms while the engine is
still warming up.
W Note
Do not leave engine idling unattended af­
ter start ing . If wa rning lights should come
on to indicate improper operation, they
wo uld go unheeded . Ex tended idling also
produces heat, wh ich could res ult in ove r­
heating or other damage to the ve hicle or
other property .
Regular maintenance
A badly tuned engine unnecessarily wastes a
lot of fuel.
• Have your veh icle serviced at reg ular in ter -
vals .
By having your ve hicle regu la rly se rviced by an
Audi dealer he lps to ensu re tha t it runs p rop ­
erly and economically . The condition of your
vehicle not only affects its safety and ability to
ho ld its va lue, it also affects
fuel con sump­
tion .
Check your oil e ach time you
fill y our tank.
The amount of o il used is re lated to engine
load and speed.
It is normal for the oil consumption of a new
engine to reach its lowest value after a certa in
mileage has bee n driven . ..,.

You must drive your vehicle about 3,000 miles (5,000 kilometers) before you can properly
assess oil consumption.
This also applies to fuel consumption and en­
gine output.
(D Note
- Have your vehicle maintained properly
and in accordance with the service rec­
ommendations in your Warranty
& Main­
tenance booklet. Lack of proper mainte­
nance as well as improper use of the ve­
hicle will impair the function of the
emission control system and could lead
to damage .
- Do not alter or remove any component of
the Emission Control System unless ap­
proved by the manufacturer.
- Do not alter or remove any device, such
as heat shields, switches, ignition wires,
valves, which are designed to protect
your vehicle's Emission Control System
and other important vehicle compo­
nents.
Fewer short trips
Fuel consumption will always be relatively
high on short trips .
.,. Try to avoid driving short distances with a
cold engine .
The engine and catalytic converter have to reach their optimal
operating temperature to
reduce fuel consumption and noxious emis­
sions effectively.
Just after starting, a cold engine in a mid-size
car only achieves a fuel economy of 6 -8 miles
per gallon (30-40 l/100 km). After about a
half a mile, fuel economy climbs to 12 mpg
(20 l/100 km). After about
2.5 miles (4 km),
the engine is at its proper operating tempera­
ture and fuel economy has reached a normal
level. So you can see that you should avoid
short trips whenever possible.
Driving and environment 205
The outside temperature is also critical in this
regard. Your car consumes more fuel in the
winter than in the summer.
•
•

206 Trailer towing
Trailer towing
Driving with a trailer
General information
Your Audi was designed primarily for passen­
ger transportation .
If you plan to tow a trailer, p lease remember
that the additional load will affect durability,
economy and performance .
Trailer towing not on ly places more stress on
the vehicle, it also calls for more concentra­
tion from the driver.
For this reason, always follow the operating
and driving instructions provided and use
common sense.
@ Note
If you are going to tow a trai ler, you must
activate the trailer operation mode
c:::> page 206, Operating instructions.
Technical requirements
Trailer hitch
Use a weight-carrying hitch conforming to the
gross trailer weight. The hitch must be suita­ ble for your vehicle and trailer and must be
mounted securely on the vehicle's chassis at a
technically sound location . Use only a trailer
hitch with a removable ball mount. Always
check with the trailer hitch manufacturer to
make sure that you are using the cor rect
hitch.
Do not use a bumper hitch.
The hitch must be installed in such a way that
it does not interfere with the impact-absorb­
ing bumper system. No modifications should
be made to the vehicle exhaust and brake sys­
tems . From time to time, check that all hitch
mounting bolts remain securely fastened.
When you are not towing a trailer, remove the
trai ler hitch ball mount. This prevents the
hitch from causing damage should your vehi­
cle be struck from behind
c:::> A.
Trailer brakes
If your trailer is equipped with a brakin g sys­
tem, check to be sure that it conforms to all
regulations.
T he trailer hydraulic brake system must not be
directly connected to the vehicle's hydraulic
brake system .
Safety chains
Always use safety chains between your veh icle
and the trailer.
Trailer lights
Trailer lights must meet all regulations. Be
sure to check with your Audi dealer for correct
wiring, switches and relays.
Mirrors
If you are unable to see the traffic behind you
using the regular outside mirrors, then you
must install extended mirrors. It is important
that you
always have clear v is ion to the rear .
A WARNING
--
After removing the trailer hitch, do not
store it in your vehicle . In case of sudden
braking, the hitch could fly forward and in­
jure you or your passengers.
Operating instructions
Maximum trailer weight
A trailer for your vehicle is limited to a typical
class 1 or class 2 trailer.
Trailer load distribution
Be sure the load in the trailer is held securely
in place to prevent it from shift ing forward,
backward or sideways.
Never allow a passenger to ride in a trailer
c:::> A in Driving instructions on page 208.
Engine cooling system
Towing a trailer makes the engine work hard­
er . It is important that the cooling system 's
performance is up to the additional load.