warning lights AUDI S4 2015 Owner's Manual

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Shift to N or P to start engine
This message appears when attempting to
start the engine if the selector lever for the
automatic transmission is not in the P or N
position. The engine can only be started with
the selector in these positions .
!!I Is the key in the vehicle?
This message appears if the master key is re­
moved from the vehicle with the engine run­
ning.
If the master key is no longer in the ve­
hicle, you cannot switch on the ignition after
stopping the engine and you also cannot start
the engine again. Moreover, you cannot lock
the vehicle from the outside with the key.
Shift to P otherwise vehicle can roll away.
Doors do not lock if lever is not in P.
This message appears for safety reasons
along with a warning signal.
It appears if the
selector lever for the automatic transmission
is not in the P position when switching off the
ignition. Move the selector lever to the P posi­
tion, otherwise the vehicle is not secured
against rolling away. You also cannot lock the
vehicle using the locking button* on the door
handle or using the remote key.
Convenience key defective! Use ignition lock
This message appears if the engine must be
started or stopped using the ignition key and
not the
I START ENGINE STOP! button.
On the road 87
Electromechanical
parking brake
Operation
The electromechanical parking broke replaces
the hand broke.
Fig. 101 Center co nsole: Parking b rake
.,. Pull on the switch@¢ fig. 101 to apply the
parking brake. The indicator lights in the
switch and • (USA models) . (Cana-
da models) in the instrument cluster illumi­
nate .
"'With the ignition switched on, step on the
brake pedal or the accelerator pedal and
press the switch @at the same time to re­
lease the parking brake. The indicator lights
in the switch and. (USA models)/ . (Can­
ada models) in the instrument cluster go
out.
Your vehicle is equipped with an electrome­
chanical parking brake. The parking brake is
designed to prevent the vehicle from rolling unintentionally and replaces the hand brake.
In addition to the normal functions of a tradi­
tional hand brake, the electromechanical
parking brake provides various convenience
and safety functions .
When starting from rest
- The integral starting assist helps you when
driving by automatically releasing the park­
ing brake ¢
page 88, Starting from rest.
-When starting on inclines , the starting as-
sist prevents the vehicle from unintentional-
ly rolling back. The braking force of the
parking brake is not released until sufficient
111>

88 On the road
driving force has been built up at the
wheels.
E mergency brake function
An emergency brake ensures t hat the vehicle
can be slowed down even if the
normal brakes
fail c::>
page 89, Emergency braking .
8_ WARNING
If a gear or a drive range (automatic trans­
mission) is engaged with the vehicle sta­
tionary and the engine running, you must in no instance accelerate or release the
clutch* carelessly. Otherwise the vehicle
will start to move immediately -risk of an
accident .
(D Tips
-If the parking brake is applied with the
ignition switched off, the indicator lights
i n the sw itch and -(USA models)/ .
(Canada models) in the instrument clus­
ter will go out after a certain per iod of
time .
- Occas iona l noises when the park ing
brake is applied and re leased a re no rma l
and are not a ca use for concern.
- Wh en the vehicle is parked, the parking
brake goes through a se lf-test cycle a t
regular intervals. Any assoc iated noises
are no rma l.
Parking
.. Press the brake peda l to stop the v ehicle .
.. Pull the switch @c::>
pag e 87, fig. 101 to set
the parking brake .
.. Automatic transmiss ion: Move the selector
lever to P .
.. Turn the eng ine off c::>
&_ .
.. Manua l transm ission: Shift into 1st gear .
.. When on incl ines or decli nes, tu rn the steer ­
i ng wheel so th at the vehicle will roll into
the curb if it begins to move .
8_ WARNING
-When you leave your vehicle -even if on­
ly briefly -always remove the ignition
key . Th is applies particularly whe n chil­
dren remain in the vehicle . Otherwise the
children could star t the eng ine , release
the par king brake or operate electrical
equipme nt (e.g. power windows). There
is the risk of an accident.
- W hen the veh icle is locked, no one -pa r­
ticularly not children should remain in
the vehicle . Locked doors make it more
difficult for emergency worke rs to get in­
to the vehicle -putting lives at risk .
· Starting from rest
The starting assist function ensures that the
parking broke is rel eased automatically upon
starting.
Stopping and appl ying parking brake
.. Pull the sw itch @c::> page 87 , fig. 101 to ap-
p ly the parking bra ke.
Starting and automatically releasing the
parking brake
.. When you start to dr ive as usual, the p ark ­
ing bra ke is automatica lly released and your
vehicle begins to move .
When stopping at a t raffic signal or stopping
in city t raffic on vehicles with an a utomatic
t ransmission, the parking brake can be ap­
plied. The vehicle does not have to be held
with the footbrake . The parking brake elimi­
nates the tendency to creep w ith a dr ive range
engaged. As soon as you drive off as usual,
the parking brake is re leased automat ically
and the vehicle starts to move .
Starting on slop es
When starting on inclines, the starting assist
prevents the vehicle from un in tent ionally roll­
ing back. The braking force of the parking
brake is not released until suffic ient driving
force has been built up at the wheels .
11>-

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Cruise control
Switching on
The cruise control system makes it possible to
drive at a constant speed starting at 20 mph (30 km/h).
0
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0
Fig . 103 Contro l lever wi th push-but ton
Fig . 104 Display: Se lected speed
.,. Pull the lever to position(!)~ fig. 103 to
swit ch the system on.
.,. Drive at the speed to be controlled.
.,. Press button @ to set that speed .
.,
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The stored speed a nd the green symbol
[ij;(i )~14 (US model)/ .. (Canadian model) are
shown in the display~
fig. 104 . The display
may vary, depending on the type of display in
your vehicle.
The speed is kept constant by modifying en­ gine power or through an active brake inter­
vention.
A WARNING
- Always pay attention to the traffic around you when the cruise control is in
operation . You are always responsib le for
your speed and the distance between
your vehicle and other vehicles.
On th e road 91
-For reasons of safety, cruise control
should not be used in the city, in stop­
and-go traffic, on twisting roads and
when road conditions are poor (such as ice, fog, gravel, heavy ra in and hydro­
plan ing) -risk of accident .
- Turn off the cruise control temporarily when enter ing turn lanes, highway exit
lanes or in construction zones.
- Please note that inadvertently ''resting" your foot on the accelerator pedal causes
the cruise control not to brake. This is
because the cruise control is overridden
by the driver's accelera tion.
- I f a brake system malfunction such as
overhea ting occurs when the cruise con­
trol system is switched on, the braking
function in the system may be switched
off . The other cruise contro l functions re­
main active as long as the indicator light
lij;(i )~14 (US models) ;a (Canad ian mod­
els) is on.
(D Tips
- Vehicles with manual transmission: You
can attain the set speed only if the gear
that is currently engaged will allow it, or
if it does not tax the engine and allows it
to run smoothly . Therefore shift into a
higher or lower gear in a timely manner .
- The brake lights illuminate as soon as
the brakes apply automatically.
Chang ing speed
.,. To increase/decrease the speed in incre­
ments, tap the lever in the
0 10 direction
~ page 91, fig.103 .
.,. To increase/decrease the speed quick ly, hold
the lever in the
0 10 direction until the de­
sired speed is displayed.
You can also press the accelerator pedal down
to increase your speed, e.g . if you want to
pass someone . The speed you saved earlier
will resume as soon as you let off of the acce l-
erator pedal. .,..

94 Transmi ssion
vehicle to accelerate without a noticeable in­
terruption in traction.
tiptronic tran smission
In the tiptronic transmission, power is trans­
ferred by a torq ue converter.
Selector lever positions
Applies to vehicles: with multitronic/5 tronic/tiptronic
Fig. 106 D isplay in the instrume nt duste r: selector
lever in position P
The se lector lever position engaged appears
next to the selector lever as well as in the in­
strument cluster display.
P - Park
In th is selector lever pos it ion the transmis­
sion is mechanically locked. Engage P only
when the vehicle is
completely stopped ¢ &
in Driving the automatic transmission on
page 96.
To shift in or o ut of pos ition P, you must first
press and hold the brake pedal and then press
the release button in the selector lever handle
while moving the se lector lever to or from P.
You can shift out of this position only with the ignition on .
R-Re verse
Select R only when the vehicle is at a full stop
and the engine is running at idle speed ¢ & in
Driving the automatic transmission on
page 96.
Before you move the selector lever to R, press
both the release button in the handle of the
selector lever
and the brake pedal at the same
time. When the
ignition is on, the backup lights i llu ­
minate when the selector lever is moved into
R .
N -Neutral
The transm iss io n is in neut ral i n this pos ition.
S hi ft to this position fo r standing with the
brakes applied ¢
& in Driving the automatic
transmission on page 96.
When the vehicle is stat ionary or a t speeds
below 1 mph (2 km/h), yo u must always app ly
the footbrake before and whi le moving the
lever o ut of N .
D/S - Normal position for driving forward
In the D/S pos ition, the transmission can be
opera ted ei ther in the norma l mode D or in
the sport mode S . To select the sport mode S,
pull the selector lever back briefly. P ulling the
lever back again will se lect the normal mode
D. The instrument cluster disp lay shows the
selected driving mode.
In the
normal mode D, the transmission auto­
matically selects the suitable gear ratio.
It de­
pends on engine load, vehicle speed and driv­
ing style.
Se lect the
s port mode S for sporty dr iving.
T he vehicle makes full use of the engine's
power. Shift ing may become noticeable when
acce lerating.
When the vehicle is stationary or at speeds below 1 mph (2 km/h), you must always app ly
the foot brake before and while moving the lever to D/S out of N.
A WARNING
Read and follow all WARNINGS ¢ .& in
Driving the automatic transmission on
page 96 .
(D Note
Coasting downhill with the transm ission in
N and the engine not running will result in
damage to the automatic transmission
and possibly the cata lytic conve rter. .,..

96 Transmission Starting the engine
.. The selecto r lever must be in P or N.
Starting off
.. Press and hold the brake pedal.
.. Press and hold the release button in these­
lector lever handle, se lect t he des ired selec­
tor lever position such as D/S and release
the button .
.. Wait briefly unti l the transmission has shift ­
ed (you will feel a slight movement) .
.. Remove your foot from the brake pedal and
acce lerate.
Stopping temporarily
.. Keep the vehicle stationary usin g the brak­
ing peda l, for examp le at traffic lights .
.. Do not press the accelerator pedal when do­
ing this .
.. To prevent the veh icle from rolling when you
start driving, set the parking brake when
stopping on steep inclines
c> _& .
.. The parking brake will release automatically
and the vehicle w ill start moving once you
press the accelerator pedal.
Stopping/parking
If the selector lever is not in the P position
when you open the dr iver's door, the vehicle
could roll. The message
Transmission: Car
may roll! Shift to park!
appears.
.. Press and hold the brake pedal until the ve-
hicle has come to a complete stop .
.. Apply the parking brake
c> page 88, Parking .
.. Select the P selector lever position c> _&.
Stopping on an incline
.. Always press the brake pedal to hold the ve­
hicle in place and prevent it from "rolling
back"
c> _& . Do not try to prevent the vehi­
cle from "roll ing back" when a gear is en­
gaged by increasing the eng ine speed
c> (D.
Starting on an incline
.. Activate the parking brake.
.. With the driving gear se lected, press the ac­
celerator pedal carefully. The park ing brake will release automatically if your seat
belt is
fastened .
Under certain circumstances, such as driving
in the mo untains, it may be usefu l to switch
temporarily to the manual shift program in or­
der to adjust the gears to the driving cond i­
tions by hand
c> page 98.
On slopes, activate the parking brake first and
then move the selector lever to the P position .
This prevents too much stress from being
placed on the locking mechanism .
Vehicles with multitronic transmission: Your
vehicle is equipped with
hill hold assist allow­
ing you to start while on an incline. The sys­
tem is activated when the brake pedal is
pressed down and he ld
for a few seconds . The
brake pressure will hold for
a moment after
the brake pedal loosens to prevent the vehicle
from roll ing backwards wh ile starting up .
A WARNING
-The vehicle can also roll when the engine
is stopped.
- Unintended vehicle movement can cause
serious injury.
- Never leave your vehicle with the engine
r un ning while in gear. If you must leave
your veh icle when the engine is running,
activate the parking brake and move the
selecto r lever to P.
- Power is still transmitted to the wheels
when the engine is running at idle. To
prevent the vehicle from "creeping", you
must keep your foot on the brake when
the engine is running and the selector
lever is in D/S or R or "tiptronic" mode is
selected .
- Do not press the accelerator pedal when changing the selector lever position
while the veh icle is stationary and the
engine is running.
- Never shift into R or P while driving.
- Before driving down a steep s lope, re-
duce your speed and shift into a lower
gear with "tiptronic".

126 Driving Saf ely
Driving Safely
General notes
Safe driving habits
Please remember -safety first!
This chapter contains important information,
tips, instructions and warnings that you need
to read and observe for your own safety, the
safety of your passengers and others . We have
summarized here what you need to know
about safety belts, a irbags, ch ild restra ints as
well as child safety. Your safety is for us
priori­
ty number 1.
Always observe the info rmat ion
and warn ings in th is sect ion -fo r yo ur own
safety as well as that of your passengers .
The information in this se ction app lies to all
model ve rsions of your veh icle . Some of the
feat ures described in this sec tions may be
standard equipment on some models, or may
be optional equipment on others. If you are
not sure, ask your authorized Audi dealer.
A WARNING
-Always make sure that you follow the in­
struct ions and heed the WARNINGS in
this Manual. It is in your interest and in
the inte rest of you r passengers.
- Always keep the complete Owner's Liter­
ature in your Audi when you lend or sell
your vehicle so that this important info r­
mation will always be ava ilable to the
dr iver and passengers.
- Always keep the Owner's literature handy
so that you can find i t eas ily if you have
ques tions.
Safety equipment
The safety features are part of the occupant
restraint system and work together to help
redu ce the risk of injury in a wide variety of
accident situations.
Your safety and the safety of your passenge rs
should not be left to chance. Advances in
technology have made a varie ty o f fea tures
avai la bl e to he lp re duce the risk of injury in an accident
. The following is a list of just a few of
the safety features in your Audi:
- sophis tic ated s afety be lts fo r drive r and a ll
passenger sea ting pos it ions,
- be lt fo rce limi ters fo r the front seats,
- belt p retensioners for the seats,
- head restra ints for each seating positio n,
- front airbags,
- side airbags in the front seats,
- side curtain a irbags,
- specia l LATCH anchorages for child re-
s tr aints,
- ad justab le steer ing colum n.
These ind iv idual safety features, can work to­
gether as a system to he lp protect you and
you r passengers in a w ide range of accidents .
T hese fe atures canno t work as a system if
they a re not always correct ly adjusted and co r­
rect ly used.
Safety i s everybody' s respon sibility!
Important things to do before driving
Safety is everybody's job! Vehicle and occu­
pant safety always depends on the informed and careful driver.
Fo r yo ur safety and the safety of your passen­
gers,
before driv ing alway s:
.,. Make sure that all lights and signa ls are op­
erati ng correctly .
.,. Make su re that the t ire p ressu re is co rrect .
.,. Make s ure that all windows are clean and af­
ford good v is ibili ty to the outs ide.
.,. Sec ure all lugg age and o ther items c aref ully
qpage 66 .
.,. Ma ke s ure that nothing can inte rfere with
the peda ls .
.,. Ad just front seat, head restraint and mirrors
correctly for your height .
.,. Instruct rear seat passengers to adjust the
head restra ints according to their he ight .
.,. Make s ure to use the r ight child restraint
co rrectly to p rotect chi ldren ¢
page 165,
Child Safety. "'

136 Safety belts
Safety belts
General notes
Always wear safety belts!
Wearing safety belts correctly saves lives!
This chapter explains why safety be lts are nec ­
essary, how they work and how to adjust and
wear them correctly .
.. Read a ll the information that fo llows and
heed all of the instructions and WARNINGS.
A WARNING
Not wearing safety belts or wearing them
improperly increases the risk of ser ious
personal in jury and death .
- Safety belts are the sing le most effective
means avai lab le to reduce the risk of se­
r ious injury and dea th in a utomob ile acci­
dents. For your protection and that of
yo ur passenge rs, always co rrectly wear
safety belts when the vehicle is moving.
- Pregnant women, injured, or physically
im paired perso ns m ust also use safety
belts. Lik e all veh icle occup ants, they are
more like ly to be ser iously injured if they
do not wea r safety be lts . The best way to
protect a fetus is to protect the mother -
throughout the entire pregnancy.
Number of seats
Your Audi has a total of five seating positions: two in the front and three in the rear. Each
seating position has a safety belt.
A WARNING
Not wea ring safety belts or weari ng them
improp erly increases the risk of ser ious
pe rsonal i njury and deat h.
- Never st rap more than one pe rson, in­
cl uding small ch ild ren, into any belt.
It is
e speci ally dange rous to pla ce a safety
belt over a child s itting on yo ur lap.
- N ever le t mo re people ride in the ve hicl e
than there are s afe ty be lts avail able. -
Be s ure everyone riding in the vehicle is
properly restrained w ith a separate safe ­
ty belt or child restra int.
Safety belt warning light
Your vehicle hos o warning system for the
driver and (on USA models only) front seat
passenger to remind you about the impor­
tance of buckling-up .
F ig. 142 Safety belt warni ng lig ht in the instrument
cluster -en larged
Before driv ing off, always :
.. Fasten yo ur safety belt and make sure you
are wearing it properly .
.. Make sure that your passengers also buck le
up and properly wear their safety be lts.
.. Protect your children wit h a child restraint
system approp riate fo r the size and age of
t he children.
The . war ning light i n the instrument clus­
ter lights up when the ig nition is switched on
as a rem inder to fasten the safety belts. In ad­
dition, you will hear a warning tone fo r a cer­
ta in pe riod of time.
Fasten your safety belt now and make sure
that your pa ssenger s also prope rly put on
their safety belts.

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Intelligent technology 187
Switching on/off
ESC turns on automatically when you start the engine .
Fig. 174 Version A: lower ce nter console,~ OFF but·
to n
The ESC is designed to function in levels. De·
pending on the level that is selected, the sta­
b ili zat ion function of the ESC is limited or
switched off . The amount of stab ilizat ion con ­
trol will differ depend ing on the level.
The following situations are exceptions where
it may be useful to switch on sport mode (Se·
dan) or offroad mode (allroad) to allow the
wheels to sp in:
Sedan: ESC levels
Fig. 175 Vers ion B: upper cente r console,~ OFF bu t·
ton
- Rocking the vehicle to free it when it is stuck
- Dr iving in deep snow o r on loose ground
- Dr iving with snow chains
- allroad : Driving on rough terrain when much
of the car's weight is lifted off the wheels
(axle articulation)
- allroad : Driving downhill while braking on
loose ground
Sport mode on ESC/ASR off Sport mode off or
ESC/ASR on
Behavior
The ESC and ASR stab iliza- The stabilization funct io n The full stab ilization func·
tion funct ions are lim ited is not available
c::> /1.. ESC tion of the ESC and ASR is
c:::> &. . and ASR are switched off. available again.
Operation Press the I~ OF FI button Press and hold the I~ OF FI Press the I~ OF FI button
briefly. button longer than 3 sec-
again.
onds .
Indicator fl turns on. II and lfilf•)H turn on . JI turns off or II and
lights If ilft)H turn off.
Driver mes- Stabilization control Stabilization control Stabilization control
sages (ESC): Sport. Warning! (ESC): off. Warning! Re- (
ESC) : On
Restricted stability stricted stability

190 Intelligent technology
overheat re ducin g the effectiveness of
the ent ire brake system.
- Failure of one brake circuit will impair
the braking capability resulting in an in­
creased stopp ing distance. Avoid driv ing
the vehicle and have it towed to the near­ est author ized Audi dealer or qualified
workshop .
- Never let the vehicle ro ll to a stop w ith
the engine shut 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, dynamic
steering
The electro-mechanical power assist helps
the driver when steering.
Power stee ring adapts electronically based on
the vehicle speed.
Indicator lights and messages
• Steering defective! Do not drive vehicle!
If this ind icator lig ht tu rns on and stays on
an d th is message appears, t he power steer ing
may have f ailed.
D o
not cont in ue d riving. See yo ur autho rized
Aud i deale r or a q ua lifi ed r epa ir facility for as­
sistance.
'1:I Dynamic steering : System fault! You can
cont inue driv ing
If the indicator light t urns on and the mes­
sage appears, the steer ing may be more diffi­
cul t to move or more se nsitive than usual. The
steer ing wheel may also be at an angle whe n
d riving straight .
Drive s low ly to your author ized Audi dealer or
q ua lified workshop to have the malfunction
cor rected .
'y.ij Dynamic steering: initializing
If this driver message appears and the indica ­
tor light is f lashing on the instrument panel,
dynam ic steer ing * is being re in it ia lized. After
starting the engine, the steering wheel will move s light ly. Re- initialization might be nec­
essary if the steering wheel was moved hard
to the left and right wh ile the vehicle was not
moving . Th e display goes out as soon as ini ti­
ali za tion is complete.
_& WARNING
Ha ve the dy namic stee ring * system m al­
f u nction repa ired as soon as possib le by an
a uthorized Audi dea ler or qua lified work ­
shop -risk of acc ident !
@ Tips
-If the . or '1:I indic ator li ght only s tays
on fo r a shor t time, you m ay continue
dr iving.
- T he dynamic s teering * stabi lit y syste ms
are no t av ail ab le in the even t of a system
ma lf u nction.
- F or ad di tion al information on dynamic
steering *, refe r to
¢page 115 .
-
Driving with your
quattro
App lies to vehicles: wi th all-w hee l drive
With a/I-wheel drive, all four wheels are driv­
en .
General information
With a ll-wheel d rive, power is distr ib uted to
all four wheels. This happens automatically
depending on your driving style and the road
co ndit ions at the time . See also
¢ page 185.
A center d ifferential distributes the driving
power variably to the front and rear axle. It
wor ks together with selective w heel torque
co ntrol, wh ich activates when dr iving t hrough
c ur ves
c::;,page 186. With the sport differe n­
t ia l* , pow er d istr ibut ion to the rea r wheels is
variable a nd can be adjusted w ith drive se lect
c::;, page 115. .,..

196 Driving and en vironm ent
Reducing unnecessary idling
Even when your car is just idling it burns up
fuel .
.,. Shut the engine off when you are not dr iving
the vehicle.
.,. Do not warm up the vehicle by letting the
engine run at idle .
It makes sense to shut
off the engine in traffic
jams, when waiting for trains to pass at ra il­
road crossings, or at traff ic lights that have
l ong wa its on red . Turning the engine
off fo r
just 30-40 seconds saves more fue l than is
burned starting the eng ine again .
It takes a long time for the engine to warm up
fu lly when it is running at idle . Howeve r, wear
and nox ious em issions are especially high
when the engine is warming up. So you should
drive away as soon as you start the engine and
avoid running at high rpms while the engine is
still warming up .
(D Note
Do not leave engine idling unattended af­
ter starting . If warning lights shou ld come
on to indicate improper operation, they
wou ld go unheeded. Extended idling also
produces heat, which cou ld result in over­
heating or other damage to the vehicle or
other property .
Regular maintenance
A badly tuned engine unnecessarily wastes a
lot of fuel .
... Have your vehicle serviced at regular inter-
vals.
By having your vehicle regularly serviced by an
authorized Audi dealer he lps to ensure that it
runs properly and economically . The condition
of your vehicle not only affects its safety and
ab ility to hold its value, it also affects
fu el
con sumpt ion .
Check you r oil ea ch time you fill you r ta nk.
The amount o f oi l used is re lated to engine
load and speed.
It i s normal fo r the oil consump tion of a new
engine to reach its lowest value after a certa in
mileage has been d riven.
You must drive your veh icle about 3,000 m iles
(S,000 kilometers) before you can properly
assess oil consumpt ion.
This also app lies to fue l consumption and en­
gine output.
(D Note
- Have your veh icle ma inta ined properly
and in accordance with the service rec­
ommendations in your Wa rranty
& Main­
t enance boo klet . Lack of p roper ma inte­
nance as well as improper use of the ve­
hicle will impair the function of the
emission contro l system and cou ld 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 sh ie lds, switches, ignition w ires,
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 dr iv ing short distances w ith a
cold engine .
T he engine and cata lytic converter have to
reach their opt imal
operat ing temperature to
reduce fuel consumpt ion and nox ious emis­
s ions effectively .
Just after starting, a co ld eng ine in a mid-s ize
car only achieves a fuel economy of 6-8 mi les
per gallon (30-40 l/100 km). After about a
half a mile, fuel economy cl imbs to 12 mpg
(20 l/100 km) . After about
2 .5 miles (4 km), ll>