Engine AUDI A4 2008 B8 / 4.G Manual PDF

Your vehicle and the environment229
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Your vehicle and the environmentRunning inA new vehicle should be run in over a distance of 1,500 km. For the
first 1,000 km the engine speed should not exceed 2/3 of the
maximum permissible engine speed – do not use full throttle and do
not tow a trailer or caravan. From 1,000 to 1,500 km you can gradu-
ally increase the engine rpm and road speed.
During its first few hours of running, the internal friction in the
engine is greater than later on when all the moving parts have
bedded down.
How the vehicle is driven for the first 1,500 km also influences the
engine quality. After the first 1,500 km you should continue driving
at moderate engine speeds, in particular when the engine is cold.
This helps to reduce wear and tear on the engine and increases the
potential mileage which can be covered by the engine.
You should also avoid driving with the engine speed too low.
Change down to a lower gear when the engine no longer runs
“smoothly”. Excessively high engine speeds are prevented by an
automatic rev limiter.Emission control systemsCatalytic converter
Applies to vehicles with petrol engine: The vehicle must only be
used with unleaded petrol, otherwise the catalytic converter will be
destroyed.
Never run the tank completely dry. The irregular fuel supply can
cause misfiring, which would allow unburnt fuel to enter the
exhaust system, which could cause overheating and damage the
catalytic converter.Diesel particulate filter
Applies to vehicles with diesel engine: The diesel particulate filter
can filter out almost all soot particles contained in the exhaust gas.
In normal driving conditions the filter is self-cleaning. Should the
self-cleaning function of the filter not be able to operate, e.g. when
the vehicle is continuously used only for short trips, the filter
becomes obstructed with soot and the symbol

for the diesel
particulate filter lights up ⇒page 38.
WARNING
•
Because of the high temperatures which can occur in the emis-
sion control system (catalytic converter or diesel particulate
filter), do not park the vehicle where the exhaust can come into
contact with flammable materials under the car (e.g. on grass or
at the forest edge). - Fire hazard!
•
Do not apply any underseal agents in the area around the
exhaust system - fire hazard!
How to improve economy and minimise pollutionFuel economy, environmental impact and wear on the engine,
brakes and tyres depend largely on the way you drive the vehicle. By
adopting an economical driving style and anticipating the traffic
situation ahead, you can reduce fuel consumption by 10-15%. The
following section gives you some tips on lessening the impact on
the environment and reducing your operating costs at the same
time.
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Your vehicle and the environment 230Anticipate well in advance
A car uses most fuel when accelerating. If you anticipate hazards
and speed changes well in advance, you will need to brake less and
thus accelerate less. Wherever possible, let the car slow down grad-
ually with a gear engaged, for instance when you can see that the
next traffic lights are red. This takes advantage of the engine
braking effect, reducing wear on the brakes and tyres. Emissions
and fuel consumption will drop to zero due to the overrun fuel cut-
off.
Change gear early to save fuel
An effective way of saving fuel is to change up quickly through the
gears. Running the engine at high rpm in the lower gears uses an
unnecessary amount of fuel.
Manual gearbox: Shift up to second gear as soon as possible. If
possible, we recommend shifting up to the next gear at approx.
2,000 rpm.
Automatic gearbox: Press the accelerator slowly and avoid using
the “kick-down” feature.
Avoid driving at high speed
Avoid travelling at top speed. Fuel consumption, exhaust emissions
and noise levels all increase very rapidly at higher speeds. Driving at
moderate speeds will help to save fuel.
Do not let the engine idle for longer than necessary
It is worthwhile switching off the engine when waiting in a traffic
jam, at level crossings or at traffic lights with a long red phase. The
fuel saved after only 30 - 40 seconds is greater than the amount of
fuel needed to restart the engine.
The engine takes a very long time to warm up when it is running at
idling speed. Mechanical wear and pollutant emissions are also
especially high during this initial warm-up phase. It is therefore best
to drive off immediately after starting the engine. Avoid running the
engine at high speed.Regular servicing
Regular servicing can establish a basis for good fuel economy
before you start driving. A well-serviced engine gives you the
benefit of improved fuel efficiency as well as maximum reliability
and an enhanced resale value. A badly tuned engine can consume
up to ten percent more fuel than necessary.
Avoid short trips
The engine and emission control system need to reach their proper
working temperature in order to minimise fuel consumption and
emissions.
A cold engine uses disproportionately more fuel. The engine only
reaches its working temperature after about four kilometres, when
fuel consumption will return to a normal level. This is the reason
why we recommend avoiding short trips wherever possible.
Maintain the correct tyre pressures
Always make sure the tyres are inflated to the correct pressures
⇒page 268 to save fuel. If the tyre pressures are just 0.5 bar too low,
this can increase the fuel consumption by as much as 5 %. Due to
the greater rolling resistance, under-inflation also increases tyre
wear and impairs handling.
Do not use winter tyres all through the year; they will increase fuel
consumption by up to 10 %.
Avoid carrying unnecessary loads
Every kilo of extra weight will increase the fuel consumption, so it is
worth checking the luggage compartment occasionally to make
sure that no unnecessary loads are being transported.
A roof carrier is often left in place for the sake of convenience, even
when it is no longer needed. At a speed of 100-120 km/h your car will
use about 12 % more fuel as a result of the extra wind resistance
caused by the roof carrier - even when it is empty.
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Your vehicle and the environment231
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data Save electrical energy
The engine drives the alternator to generate electricity. This means
that fuel consumption rises when more power is required for elec-
trical equipment. Switch off electrical equipment when it is not
needed. Electrical equipment which uses a lot of electricity includes
the blower (at a high setting), the rear window heating and the seat
heating*.
Environmental compatibilityEnvironmental protection is a top priority in the design, choice of
materials and production of your new Audi.
Design measures for economical recycling•
Joints and connections designed for ease of dismantling
•
Modular construction to facilitate dismantling
•
Increased use of single-grade materials
•
Plastic parts and elastomers are labelled in accordance with ISO
1043, ISO 11469 and ISO 1629
Choice of materials
•
Nearly all materials used can be recycled
•
Similar types of plastics grouped together for easy recycling
•
Recycled materials used in manufacture
•
Reduced vapour emissions from plastics
•
CFC-free refrigerant in air conditioner
Compliance with the laws prohibiting the use of: Cadmium,
asbestos, lead, mercury and chrome VI.
Manufacturing methods
•
Using recycling material for manufacturing plastic parts
•
Solvent-free cavity sealing
•
Solvent-free wax for protecting the vehicles in transit
•
Solvent-free adhesives
•
No CFCs used in production
•
Surplus materials used extensively for energy conversion and
building materials
•
Overall water consumption reduced
•
Heat recovery systems
•
Water-soluble paint
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Towing a trailer 232Towing a trailerDriving the vehicle with a trailer or
caravanTechnical requirements
The towing bracket must comply with certain technical
requirements.Your car is intended mainly for transporting passengers and
luggage. However, if suitably equipped, it can also be used to tow a
trailer or caravan.
If the car is supplied with a factory-fitted towing bracket it will
already have the necessary technical modifications and meet the
statutory requirements.
A 13-pin socket is provided to make the electrical connection
between the car and the trailer. If the trailer has a 7-pin plug you can
use an adapter cable. This is available from Audi dealers.
WARNING
If a towing bracket is retrofitted, the installation should be carried
out by a qualified workshop.•
In particular in high outside temperatures it is not possible to
drive up long steep gradients without a suitable cooling system.
The engine would then overheat.
•
Incorrect installation can result in a safety risk.
Points to check before towingTrailer weights
Never exceed the maximum permitted trailer weights ⇒page 323.If you do not load the trailer up to the maximum permitted trailer
weight, you can then climb correspondingly steeper gradients.
The maximum trailer weights listed are only applicable for altitudes
up to 1000 m above sea level. With increasing altitude the engine
power and therefore the car's climbing ability are impaired because
of the reduced air density, so the maximum trailer weight has to be
reduced accordingly. The weight of the car and trailer must be
reduced by 10% for every further 1000 m (or part thereof). This
figure refers to the combined weight of the (loaded) vehicle and
(loaded) trailer.
The figures for the draw bar weight that appear on the identification
plate of the towing bracket are for certification purposes only. The
correct figures for your specific vehicle, which may be lower than
these figures for the towing bracket, are given in the registration
documents. Also refer to ⇒page 323.
Distributing the load
Distribute loads in the trailer so that heavy objects are as near to the
axle as possible. Loads carried in the trailer must be secured to
prevent them slipping.
Where possible, operate the trailer with the maximum permitted
draw bar weight on the ball joint of the towing bracket, but do not
exceed the specified limit.
Tyre pressure
Check the tyre pressures on your car and adjust for “full load” condi-
tions (refer to the sticker listing the tyre pressures on the end face
of the driver's door). It may also be necessary to adjust the tyre pres-
sures on the trailer according to the recommendations of the trailer
manufacturer.
Exterior mirrors
Check whether you can see enough of the road behind the trailer
with the standard mirrors. If this is not the case you should have
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Towing a trailer 234•
The trailer overrun brake must be set correctly. This is important
to ensure that the trailer can be braked correctly, to avoid the vehicle
and trailer “jack-knifing” and to prevent excess braking of the trailer.
•
At low outside temperatures, both the towing vehicle and the
trailer should be fitted with winter tyres.
WARNING
It is essential that you adjust your speed to suit the weather, road
and traffic conditions. Do not let the trailer stabilisation system
tempt you into taking any risks when driving – this can cause acci-
dents.•
The ESP and trailer stabilisation system cannot defy the laws
of physics. This should be kept in mind, particularly on slippery
and wet roads and when towing a trailer with a light load.
•
The trailer stabilisation system is functional, regardless of
whether the trailer has a mechanical overrun brake or not.
•
The trailer stabilisation system is not always able to detect
swaying of trailers with a light load and will therefore not inter-
vene.
•
A trailer can still “jack-knife” on slippery roads with little grip,
even if the towing vehicle is equipped with the trailer stabilisation
system.
•
Trailers with a high centre of gravity may even tip over before
they start to sway sideways.
•
If you are not towing a trailer, but the trailer socket is being
used (e.g. for an illuminated bicycle rack), the trailer stabilisation
system may be activated in extreme driving conditions.
•
Please note the additional information and warnings
⇒page 234.
Notes on towing
Driving with a trailer always requires extra care.Weight distribution
Try to avoid towing a loaded trailer with an unladen vehicle. If this
cannot be avoided, drive extra slowly to allow for the unbalanced
weight distribution.
Speed
The stability of the car and trailer is reduced with increasing speed.
For this reason it is advisable not to drive at the maximum permis-
sible top speed in unfavourable road, weather or wind conditions.
This applies especially on a downhill gradient.
You should always reduce speed immediately if the trailer shows
the slightest sign of swaying. Never try to stop the swaying by accel-
erating further.
Always brake in good time. If the trailer has an overrun brake, apply
the brakes gently at first and then firmly. This will prevent the jerking
that can be caused by the trailer wheels locking. Change down in
good time before going down a steep hill so that you can use the
engine braking effect to slow down the vehicle.
Swaying and pitching can be reduced by stabiliser aids. We recom-
mend having stabiliser aids installed when towing trailers with a
high trailer weight. They can be purchased and installed at an Audi
dealer.
Overheating
When climbing long hills in hot weather with the engine running
fast in low gear, you should keep an eye on the coolant temperature
gauge ⇒page 11. Reduce speed immediately if the needle moves to
the top end of the scale. If the temperature warning lamp
 in the
instrument cluster should start flashing, stop the car and let the
engine cool down by running it at idling speed for a few minutes.
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Fuel and filling the tank251
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Fuel and filling the tankPetrolApplies to vehicles: with petrol enginePetrol grade
The correct grade of petrol is listed inside the fuel tank
flap.The vehicle is equipped with a catalytic converter and must only be
run on unleaded petrol. Unleaded petrol must comply with the
European EN 228 standard. The petrol grades have different octane
ratings (RON). If, in exceptional circumstances, the correct octane
rating is not available, please note the following:•
For engines which require Premium unleaded petrol (95 RON)
according to ⇒page 323, “Performance, weights and dimensions”:
Regular unleaded fuel with 91 RON can also be used. This will,
however, result in a slight loss of power.
•
For engines which require Super Plus unleaded petrol (98 RON)
according to ⇒page 323, “Performance, weights and dimensions”:
Premium unleaded fuel with 95 RON can also be used. This can,
however, result in a slight loss of power under certain driving condi-
tions. – If premium unleaded petrol is not available, the engine can
be run on regular unleaded petrol with 91 RON as an emergency
measure. In this case only use moderate engine speeds and a light
throttle. Fill up with premium or Super Plus petrol as soon as
possible.Caution
•
Petrol complying with the EN 228 standard can contain small
quantities of ethanol. However, “bioethanol fuels”, which are
retailed under various different names such as E50 and E85, and
which contain a large proportion of ethanol, must not be put into
the vehicle, as this would damage the fuel system.
•
Even one tankful of leaded fuel would permanently impair the
efficiency of the catalytic converter.
•
High engine speed and full throttle can damage the engine when
using petrol with an octane rating lower than the correct grade for
the engine.
DieselApplies to vehicles: with diesel engineDiesel fuel
Please note the information on the inside of the fuel tank
flap.Diesel fuel must comply with the European EN 590 standard. It must
have a cetane number (CN) of at least 51. The cetane number indi-
cates the ignition quality of the diesel fuel.
Winter-grade diesel
Diesel fuel can thicken in winter. For this reason petrol stations in
some countries also offer winter diesel.
Caution
•
The vehicle is not designed for the use of biodiesel (FAME fuel).
The fuel system would be damaged if you used biodiesel.
•
Do not mix fuel additives (“thinners”, petrol or similar additives)
with the diesel fuel.
•
If poor-quality diesel fuel is used, it may be necessary to drain
the water separator on the fuel filter more frequently than is speci-
fied in the Service Schedule. We recommend having this done by a
specialist workshop. If water is allowed to collect in the filter, this
can cause engine performance problems.
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Fuel and filling the tank253
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data −Insert the filler nozzle as far as possible into the spare fuel
canister.
−If the spare fuel canister is made of metal, the filler nozzle
must be in contact with the canister during filling. This helps
prevent an electrostatic charge building up.
−Make sure you never spill fuel in the vehicle or in the luggage
compartment. Fuel vapour is explosive. Risk of fatal accident!
Caution
•
If any fuel is spilt onto the vehicle, it should be removed immedi-
ately, as it could otherwise damage the paintwork.
•
Never run the tank completely dry. If there is an irregular fuel
supply, misfiring can occur. As a result unburnt fuel can enter the
exhaust system and cause damage to the catalytic converter(s).
•
When filling the fuel tank after having run it completely dry on a
vehicle with a diesel engine the ignition must be switched on for at
least 30 seconds without starting the engine. When you then start
the engine it may take longer than normal (up to one minute) for the
engine to start firing. This is because air needs to be bled from the
fuel system while starting.For the sake of the environment
Do not try to put in more fuel after the automatic filler nozzle has
switched off; this may cause the fuel to overflow if it becomes warm.
Note
The tank flap is not locked when you lock the vehicle from the
inside.
Releasing the tank flap manually
The tank flap can be released manually if the central
locking system should fail to operate.The manual release mechanism is located behind the side
trim on the right of the luggage compartment.
– Open the right-hand side trim.
– Release the ring from its holder and pull the ring
⇒fig. 249. You should now be able to open the tank flap
in the usual way ⇒page 252.
WARNING (continued)
Fig. 249 Luggage
compartment:
Releasing the fuel tank
flap manually
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Checking and topping up fluids 254Checking and topping up fluidsBonnetReleasing the bonnet
The bonnet is released from inside the vehicle.– Open the driver's door.
– Pull the lever under the dashboard in the direction indi-
cated (arrow) ⇒fig. 250.The bonnet springs out of its lock.
Opening the bonnetBefore opening the bonnet make sure that the windscreen
wiper arms are not lifted away from the glass. Otherwise the
paint may get damaged.
– Lift the bonnet slightly ⇒.
– Press the release catch under the bonnet upwards
⇒fig. 251. This will release the arrester hook.
– Open the bonnet.The bonnet is held open by two gas-filled struts.
WARNING
To avoid the risk of being scalded, never open the bonnet if you see
steam or coolant escaping from the engine compartment. Wait
until no steam or coolant can be seen before opening the bonnet.
Fig. 250 Detail of foot-
well on driver's side:
Release lever
Fig. 251 Release catch
under the bonnet
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Checking and topping up fluids255
Controls
Safety
Driving tips
General maintenance
Self-help
Technical data
Working on components in the engine compartment
Extra caution is necessary when working on components
in the engine compartment.Always be aware of the danger of injury and scalding as well as the
risk of accident or fire when working in the engine compartment
(e.g. when checking and refilling fluids). Always observe the warn-
ings listed below and follow all normal safety precautions. The
engine compartment of any motor vehicle is a potentially
hazardous area. ⇒.
WARNING
•
Switch off the engine.
•
Remove the ignition key.
•
Apply the parking brake.
•
Put the gear lever in neutral or selector in P.
•
Wait for the engine to cool down.
•
Keep children away from engine compartment.
•
Never spill fluids on hot engine components. These fluids can
cause a fire (e.g. radiator anti-freeze).
•
Take care not to cause short circuits in the electrical system,
especially when working on the battery.
•
Do not touch the radiator fan when the engine is hot. The fan
may start running suddenly.
•
Do not unscrew the cap on the expansion tank when the engine
is hot. The cooling system is under pressure.
•
Protect face, hands and arms by covering the cap with a large,
thick rag to protect against escaping coolant and steam.
•
If any tests have to be performed with the engine running,
there is an extra safety risk from the rotating parts, such as the
drive belts, alternator and radiator fan, etc., and from the high-
voltage ignition system.
•
Vehicles with automatic gearbox: Never open the throttle inad-
vertently (for instance by hand from the engine compartment) if a
gear is engaged while the vehicle is stationary with the engine
running. The vehicle could otherwise start moving immediately
and possibly cause an accident.
•
Observe the following additional warnings if work on the fuel
system or the electrical system is necessary:
−Always disconnect the battery.
−Do not smoke.
−Never work near naked flames.
−Always keep an approved fire extinguisher immediately
available.Caution
When topping up fluids make sure the correct fluid is put into the
correct filler opening. This can otherwise cause serious malfunc-
tions or engine damage.
For the sake of the environment
Inspect the ground underneath your vehicle regularly so that any
leaks are detected at an early stage. If you find oil spots or other
fluids, have your vehicle inspected by a qualified workshop.
Note
On right-hand drive vehicles* some of the containers / reservoirs
mentioned below are located on the other side of the engine
compartment.
WARNING (continued)
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Checking and topping up fluids 256Closing the bonnet– To close the bonnet, pull it down to overcome the spring
pressure.
– Then let it drop into the catches; do not press down ⇒.
WARNING
•
For safety reasons the bonnet must always be completely
closed when the vehicle is moving. After closing it always check
that it is properly secured. The bonnet must be flush with the adja-
cent body panels.
•
Should you notice that the bonnet is not safely secured when
the vehicle is moving, stop the vehicle immediately and close the
bonnet properly, otherwise it could cause an accident.
Engine compartment layoutEngine compartment layout
Main components for checking and refillingFig. 252 Typical locations of fluid containers, engine oil dipstick and engine oil
filler cap
Jump-start terminal (+) under a cover . . . . . . . . . . . . .
Brake fluid reservoir (
) . . . . . . . . . . . . . . . . . . . . . . . .
Engine oil filler cap (

) . . . . . . . . . . . . . . . . . . . . . . . .
Engine oil dipstick* (orange) . . . . . . . . . . . . . . . . . . . . .
Radiator expansion tank () . . . . . . . . . . . . . . . . . . . . .
Jump-start terminal (-) with hexagon head . . . . . . . . .
Windscreen washer container (
) . . . . . . . . . . . . . . . .
Hydraulic fluid reservoir for power steering . . . . . . . .
A1
265, 294
A2
262
A3
259
A4
258
A5
261
A6
265, 294
A7
267
A8
225
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