2012 Seat Mii catalytic converter

120Starting, changing gears, parking
WARNING
The components of the exhaust system reach very high temperatures.
This could cause a fire and considerable damage.
● Always park your vehicle so that no part of the exhaust system can
come in contact with flammable materials (such as wood, leaves, spilled
fuel, dried grass, etc).
● Never apply additional underseal or anti-corrosion coatings to the ex-
haust pipes, catalytic converter or the heat shields on the exhaust sys-
tem.

Ignition lock
Fig. 83 Vehicle key positions
Vehicle keys ⇒ Fig. 83 No key in the ignition lock: The steering lock may be activated.0Ignition switched off. Key can be removed from the vehicle.1Ignition is switched on. The steering lock can be unlocked.2Switch on the engine. Release the key when the engine has star-
ted. When it is released, the key returns to position 1.
Key not authorised for the vehicle
If a key which is not authorised for this vehicle is inserted in the ignition
lock, it can be removed as follows:
●
Automatic gearbox : the key cannot be removed from the ignition lock.
Press and release the selector lever locking button. Key can be removed
from the vehicle.
● Manual gearbox: Remove the key from the ignition. 

121
Starting, changing gears, parking
WARNING
Unsuitable or careless use of the vehicle key could result in serious in-
jury.
● Always take all the keys with you whenever you leave the vehicle. The
engine could accidentally be started and electrical equipment such as
the windows could accidentally be operated resulting in serious injury.
● Never leave children or disabled people alone in the vehicle. They
could be trapped in the vehicle in an emergency and will not be able to
get themselves to safety. For example, depending on the time of the
year, temperatures inside a locked and closed vehicle can be extremely
high or extremely low resulting in serious injuries and illness or even
death, particularly for young children.
● Never remove the key from the ignition if the vehicle is in motion. The
steering may lock and it will not be possible to turn the steering wheel.
Note
● If the key is left in the ignition lock with the engine off for long periods,
the vehicle battery will run flat.
● For automatic gearbox vehicles the key can only be removed from the ig-
nition lock if the gear selector lever is in position P. In this case, press and
release the selector lever locking button. 
Starting the engine
Complete operations only in the sequence given.
1.Press the brake pedal and keep pressed until step 5 has been completed.
1 a.In vehicles with a manual gearbox: Press the clutch pedal all
the way and keep pressed until the engine starts.
Complete operations only in the sequence given.
2.Put the gearbox lever in neutral or the selector lever in posi- tion P or N.
3.Turn the key in the ignition lock to position ⇒ Fig. 83 2; do
not press the accelerator.
4.When the engine has started, release the key in the ignition lock.
5.If the engine does not start, stop the process and try again af-ter one minute.
6.Release the handbrake when you want to begin driving⇒ page 134.
WARNING
Never leave the vehicle unattended if the engine is running. The vehicle
could move off suddenly, especially if it is in gear, resulting in an acci-
dent and serious injury.
WARNING
Cold start sprays could explode or cause a sudden increase in the engine
speed.
● Never use start boosters.
CAUTION
● An attempt to start the engine while driving or starting the engine imme-
diately after turning it off can cause damage to the engine or starter motor.
● When the engine is cold, avoid high revs and heavy acceleration and do
not make the engine work hard.
● Do not push or tow start the engine. Sunburnt fuel could damage the
catalytic converter. 
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145
Starting, changing gears, parking
Moderate use of additional electrical appliances
It is important to travel in comfort, but convenience systems should be used
in an ecological manner.
Some equipment, when connected, increase fuel consumption considera-
bly, for example:
● Air conditioning cooling system: If the air conditioning system is re-
quired to cool to significantly lower temperatures than the true outside tem-
perature, it will require a large quantity of energy from the engine. There-
fore, we recommend that the selected temperature for the vehicle is not too
different to the outside temperature. It is a good idea to open all the win-
dows of the vehicle before starting your journey, and to drive a short dis-
tance with all the windows open to allow the vehicle to cool down slightly.
Only then should you close all the windows and switch on the air condition-
ing system. Keep windows closed when travelling at high speeds. Driving
with the windows open increases fuel consumption.
● Switch off the seat heating when the seats have warmed up.
● Switch off the heated rear window when it is not moist or covered in ice.
Other factors which increase fuel consumption (examples):
● Fault in engine management.
● Driving on hills. Saving fuel while driving
Fig. 92 Fuel consump-
tion in litres per 100 km
at 2 different outside
temperatures
By adopting an economical driving style and anticipating the traffic situa-
tion ahead, you can easily reduce fuel consumption by 10-15%.
A vehicle uses most fuel when accelerating. By anticipating the traffic situa-
tion ahead, you will brake and therefore accelerate less. Wherever possible,
let the vehicle roll slowly to a stop, for instance when you can see that the
next traffic lights are red.
Avoid short journeys
Fuel consumption is much higher when the engine is cold, immediately af-
ter it has been started. It takes a few kilometres of driving for the engine to
warm up and to normalise consumption.
The engine and catalytic converter need to reach their proper working tem-
perature in order to minimise fuel consumption and emissions. The ambient
temperature has a decisive influence.
Fig. 92 shows the difference in consumption for the same journey at +20 °C
(+68 °F) and at -10 °C (+14 °F). 
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173
At the filling station
lights upGauge position
⇒ Fig. 105Possible cause ⇒ Solution
 a)Red mark (ar-
row)The fuel tank is almost
empty.
The reserve tank is being
used ⇒ page 290.Refuel as soon as
possible ⇒ .
–The vehicle is running in
natural gas operating
mode.–
a)This only applies to vehicles with the fuel gauge on the instrument panel ⇒ Fig. 105.
flashes
for about 10 sec- ondsState of the barsPossible cause ⇒ Solution
 and
the seg-
ments re-
maining a)Reserve zone
(four small seg- ments)The fuel tank is almost
empty.
The reserve tank is being
used ⇒ page 290.Refuel as soon as
possible ⇒ .
–The vehicle is running in
natural gas operating
mode.–
a)This only applies to vehicles with the fuel gauge on the instrument panel display.
Several warning and control lamps light up for a few seconds when the igni-
tion is switched on while a test of the function is being carried out. They will
switch off after a few seconds.
In natural gas engines
The warning lamp  lights up when both fuel types (petrol and natural gas)
have reached reserve level.
The warning lamp  lights up when the vehicle is running in natural gas op-
erating mode. The warning lamp 
switches off when the natural gas is exhausted. The
engine changes to operate with petrol.
Problem: If the vehicle is left parked for a long time immediately after refuel-
ling, the gas level indicator does not accurately indicate the same level
shown after refuelling when the vehicle is started up again. This is not due
to a leak in the system, but to a drop in pressure in the gas tank for techni-
cal reasons after a cooling phase immediately after refuelling.
WARNING
Driving with insufficient fuel reserve could result in the vehicle breaking
down in traffic and a serious accident.
● If the fuel level is too low then the fuel supply to the engine can be-
come irregular especially on slopes.
● If the engine “is choked” or stalls due to lack of or irregularity of the
fuel supply, the power steering as well as all of the driver assistance sys-
tems including braking assistance will stop working.
● Always refuel when there is only one quarter of the fuel tank left to
avoid running out of fuel.
CAUTION
● Always pay attention to any lit lamps and to the corresponding descrip-
tions and instructions to avoid damage to the vehicle.
● Never run the fuel tank completely dry. An irregular fuel supply may lead
to ignition faults and unburnt fuel could enter the exhaust system. This
could damage the catalytic converter.
Note
The arrow next to the fuel pump symbol on the instrument panel ⇒ Fig. 105
indicates the side of the vehicle on which the fuel tank plug is located. 
Vehicle diagramPrior to a journey...While drivingCare, cleaning and mainte-
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178At the filling station
Not all petrol additives have been shown to be effective. The use of unsuita-
ble petrol additives could seriously damage the engine and the catalytic
converter. Petrol additives with metal additives must never be used.
Available petrol additives for improvements in Anti-detonation ratings or oc-
tane ratings may contain metal additives ⇒ 
.
SEAT recommends “Genuine SEAT Additives for petrol engines”. These addi-
tives are available from Specialised workshops, who will inform you of their
application.
CAUTION
● Only use fuel with an octane rating that is in line with the norm EN 228,
otherwise significant damage could be caused to the engine and fuel sys-
tem. Furthermore, it could lead to a loss of performance with the conse-
quent engine fault.
● The use of unsuitable petrol additives could seriously damage the en-
gine and the catalytic converter.
● If, in exceptional circumstances, petrol with a lower octane rating to that
recommended is used, only use moderate engine speeds and a light throt-
tle. Avoid using full throttle and overloading the engine. Otherwise engine
damage may occur. Fill up with fuel of a suitable octane rating as soon as
possible.
● Do not refuel if the filler indicates that the fuel contains metal. LRP (lead
replacement petrol) fuels also contain high concentrations of metal addi-
tives. This could damage the engine!
● Just filling one full tank of leaded fuel or with other metal additives
would seriously impair the efficiency of the catalytic converter and could
damage it. 
Natural gas
Natural gas, in addition to others, can be in liquid form. Liquefied natural gas (LNG) is the result of heavy cooling of natural gas.
Therefore its volume is considerably reduced compared with compressed
natural gas (CNG). In vehicles with a natural gas engine, liquefied natural
gas cannot be directly refilled, given that the gas would expand excessively
in the vehicle gas tank.
Therefore, vehicles with a natural gas engine must only be refuelled using
compressed natural gas
⇒ 
.
Natural gas quality and consumption
Natural gas is divided into the groups H and L depending on its quality.
Gas type H has a superior heating power and inferior nitrogen and carbon
dioxide content than type L. The higher the heating power of the natural
gas, the lower the consumption will be.
However, the heating power and the proportion of nitrogen and carbon di-
oxide can fluctuate within the quality groups. Therefore, vehicle consump-
tion can also vary when using one type of gas only.
The engine management automatically adapts to the natural gas used ac-
cording to its quality. Therefore, different quality gases can be mixed in the
tank, without the need for comprehensive draining before applying a differ-
ent quality gas.
Natural gas and safety
If you can smell gas or suspect that there is a leak ⇒ 
:
● Stop the vehicle immediately.
● Switch the ignition off.
● Open the doors to appropriately ventilate the vehicle.
● Immediately extinguish cigarettes.
● Move away from the vehicle or switch off objects that may cause sparks
or a fire.
● If you continue to smell gas, do not continue driving!
● You should obtain professional assistance. Have the fault repaired. 

187
In the engine compartment
● Open the bonnet  ⇒  page 180.
● The engine oil filler mouth can be recognised by the symbol  on the
cap ⇒ Fig. 112 and the dipstick by its coloured handle.
Check the engine oil level
● Pull out the dipstick and wipe it on a clean cloth.
● Replace the dipstick, pushing it in as far as it will go. If the dipstick to
measure engine oil has a mark, when you reintroduce it this mark should
slot into the corresponding groove located on the upper end of the tube.
● Remove the dipstick again and check the engine oil level ⇒ table on
page 187.
● After reading the oil level, replace the dipstick in the tube completely.
Engine oil topping up ranges
Fig. 111Operations required depending on the engine oil topping
up level:
Area ADo not top up oil
⇒ .Area BYou can add oil, but keep the level in this zone.
Area COil
must be added. After topping up the oil level should be
in area B.
Adding oil after checking the level
Only add engine oil in small quantities and in steps.
●
Unscrew the cap from engine oil filler mouth on the cylinder head
⇒ Fig. 112. If you are not sure where the cap is, request help from a special-
ist.
● Only refill using approved SEAT engine oil in small quantities (no more
than 0.5 ltr) ⇒ page 185.
● To avoid adding too much oil, each time you add a quantity, wait until
the oil has flowed into the crankcase so that it can be measured with the
dipstick.
● Check the oil level before adding any more oil. Do not top up with too
much engine oil ⇒ 
. ●
When the oil level is in at least the ⇒ Fig. 111 B
zone, insert the dip-
stick into the tube fully to avoid engine oil escaping when the engine is run-
ning.
● After topping up the oil, ensure that the cap is screwed on to the filler
mouth correctly.
WARNING
Oil could catch fire if it comes into contact with hot engine components.
This could lead to a fire, explosion and severe injuries.
● Always ensure that after topping of oil, the engine oil filler cap is cor-
rectly tightened. This will avoid engine oil spilling onto hot engine parts
when the engine is running.
CAUTION
● If the engine oil level is above the area A do not start the engine. You
should obtain professional assistance. Otherwise catalytic converter and
engine damage may occur.
● When refilling or changing service liquids, ensure that you put the liq-
uids into the right tank. Making a mistake when refilling could cause seri-
ous malfunctions and damage the engine!
For the sake of the environment
The oil level must never be above area A. Otherwise oil can be drawn in
through the crankcase breather and escape into the atmosphere via the ex-
haust system. 
Engine oil consumption
The consumption of engine oil can be different from one engine to another
and can vary during the useful life of the engine. 
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204Vehicle care and maintenance
WARNING
Additional underseal or anti-corrosion products could catch fire due to
the high temperatures reached by the exhaust gas system and other en-
gine components.
● Do not apply additional underseal or anti-corrosion products to the
exhaust pipes, catalytic converters, heat shields or other parts of the ve-
hicle which reach high temperatures.

Cleaning the engine compartment
The engine compartment of any motor vehicle is a potentially hazardous
area ⇒ page 180. The engine compartment should only be cleaned by qualified personnel. If
it is not correctly cleaned, the anti-corrosion coating and consequently elec-
trical components may be damaged. Moreover, water may filter directly into
the vehicle interior through the water chamber ⇒ 
.
If the engine compartment is very dirty, always take the vehicle to a Special-
ised workshop for professional cleaning. SEAT recommends visiting a Tech-
nical Service.
Water box
The water box is in the engine compartment, between the windscreen and
the engine, and beneath a perforated cover. Air is taken in through the wa-
ter box from outside to the vehicle interior via the heating and air condition-
ing system.
Leaves and other loose objects should be regularly cleaned away from the
water box either by hand or with a vacuum.
WARNING
When working on the engine or in the engine compartment, there is a
risk of injury, burns, accident or fire.
● Before starting work, please ensure you are familiar with the required
procedure and the safety precautions ⇒ page 180.
● SEAT recommends you have this work performed by a specialised
workshop.
CAUTION
If water is manually poured into the water box (for example, using a high
pressure cleaning appliance), this could cause significant damage to the ve-
hicle.
For the sake of the environment
Only wash the engine compartment in areas allocated for this purpose, to
prevent dirty water which may be contaminated by oil, grease or fuel, from
entering the drains. In some districts, the engine compartment may not be
washed outside the wash bays provided for this purpose. 

236Vehicle care and maintenance
Engine management and exhaust gas
purification system
Introduction
Additional information and warnings:
● Changing gear ⇒  page 124
● Refuelling ⇒  page 171
● Fuel ⇒ page 177
● Engine oil ⇒ page 185
● Vehicle battery ⇒ page 193
● Information stored in the control units ⇒ page 222
● Tow-starting and towing away ⇒ page 276
WARNING
The components of the exhaust system reach very high temperatures.
This could cause a fire.
● Always park your vehicle so that no part of the exhaust system can
come in contact with flammable materials (such as dried grass).
● Never apply additional underseal or anti-corrosion coatings to the ex-
haust pipes, catalytic converter or the heat shields on the exhaust sys-
tem.
 Control lamps
lights
upPossible causeSolution
Fault in engine management
(Electronic Power Control).Take the vehicle to a Specialised
workshop as soon as possible
and have the engine checked.
Fault in catalytic converter.
You should reduce speed accord-
ingly. Drive carefully until you
reach the next Specialised work-
shop. Have the engine checked
there.
flashesPossible causeSolution

Combustion fault which could
damage the catalytic convert-
er.You should reduce speed accord-
ingly. Drive carefully until you
reach the next Specialised work-
shop. Have the engine checked
there.
Several warning and control lamps light up for a few seconds when the igni-
tion is switched on while a test of the function is being carried out. They will
switch off after a few seconds.
CAUTION
Always pay attention to any lit lamps and to the corresponding descriptions
and instructions to avoid damage to the vehicle.
Note
While the control lamps  or  maintain lit up, the engine will present
faults, a higher consumption of fuel and a loss of engine power. 