tire pressure PORSCHE BOXSTER 2005 2.G Owners Manual

5
Tire Pressures for Cold Tires Summer tires and snow tires These tire pressures are valid only for Porsche approved tires.
For replacement tires it is imperative that you consult the Technical Data and Tires, Wheels
sections of this manual and follow the recommendations found there. 17 inch wheels front 29 psi (2.0 bar)
rear 36 psi (2.5 bar)
18 inch wheels front 29 psi (2.0 bar)
rear 36 psi (2.5 bar)
19 inch wheels front 32 psi (2.2 bar)
rear 36 psi (2.5 bar)

56
Controls, Instruments
Operation of the ABS system A wheel speed sensor is mounted to each of the
four wheels. If wheel lock-up of either of the front
wheels or the rear wheels is sensed during bra-
king, the brake pressure is adjusted automatically
until the wheel no longer slips. The brake pressure
is regulated for each front wheel individually and
for both of the rear wheels together.
On a road surface which is slippery on only one si-
de, the rear wheel which is braking on the slippery
surface determines the brake pressure which will
be applied equally to both rear wheels. This ensu-
res that directional stability is maintained. Howe-
ver, if braking forces approach the wheel lock-up
point for all wheels (panic braking) the ABS system
will intervene to provide a rapid rythmic braking.
The proper operation of ABS is perceived by the
driver as a pulsating brake pedal in conjunction
with audible noise and perhaps some vibration.
fIf you experience these sensations while dri-
ving or a road surface with questionable trac-
tion, reduce vehicle speed appropriate for the
prevailing road conditions.
The functional readiness of all the main electrical
components of the ABS is checked by an electro-
nic monitoring system both before and while you
drive. When the ignition is switched on the ABS warning
light will light up while the system is electronically
interrogated and goes out when the engine is star-
ted if the check is not yet complete.
If the ABS warning lamp fails to go out, this indica-
tes that ABS has been deactivated due to a fault.
If the warning lights in the instrument panel and on-
board computer light up while you are driving, this
indicates that a fault has occurred. In both cases,
normal braking, as in vehicles without ABS, is still
retained.
The ABS system should, however, be examined at
an authorized Porsche dealer immediately to pre-
vent the occurrence of further faults.
fIf the ABS system becomes inoperative, take
your vehicle to your authorized Porsche dealer
immediately.
Warning!
The control unit of the ABS brake system is
set for standard tire size. If non-standard ti-
res are installed, the control unit may misin-
terpret the speed of the vehicle, because of
the variant data it receives from the sensors
on the axles.
fUse only tire makes and types tested by Porsche.
Warning light USA
Warning light Canada

Maintenance, Car Care
177
Fuel Economy Fuel economy will vary depending on where,
when and how you drive, optional equipment
installed, and the general condition of your
car.
A car tuned to specifications and correctly
maintained, will help you to achieve optimal
fuel economy.
fHave your vehicle tuned to specifications.
Air cleaner should be dirt free to allow proper
engine “breathing”.
Battery should be fully charged.
Wheels should be properly aligned.
Tires should be inflated at correct pressure.
fAlways monitor your fuel consumption.
fDrive smoothly, avoid abrupt changes in speed
as much as possible.
fAvoid jack rabbit starts and sudden stops.
fDo not drive longer than necessary in the lower
gears. Shifting into a higher gear early without
lugging the engine will help save fuel.
fProlonged “warm up” idling wastes gas. Start
the vehicle just before you are ready to drive.
Accelerate slowly and smoothly.
fSwitch off the engine if stationary for longer
periods (traffic lights, jams, level crossings). fAny additional weight carried in the vehicle re-
duces fuel economy. Always keep cargo to a
minimum and remove all unnecessary items.
fOrganize your trips to take in several errands
in one trip.
fAll electrical accessories contribute to increa-
sed fuel consumption.
fOnly switch on the air conditioning when neces-
sary.
The EPA estimated m.p.g. is to be used for
comparison purposes, actual mileage may
be different from the estimated m.p.g., de-
pending on your driving speed, weather con-
ditions and trip length. Your actual highway
mileage will probably be less than the esti-
mated m.p.g.
fPlease observe all local and national speed li-
mits.
Operating Your Porsche in other
Countries Government regulations in the United States and
Canada require that automobiles meet specific
emission regulations and safety standards. There-
fore, cars built for the U.S. and Canada differ from
vehicles sold in other countries.
If you plan to take your Porsche outside the conti-
nental limits of the United States or Canada, there
is the possibility that
– unleaded fuel may not be available;
– unleaded fuel may have a considerably lower
octane rating. Excessive engine knock and se-
rious damage to both engine and catalytic con-
verters could result;
– service may be inadequate due to lack of pro-
per service facilities, tools or diagnostic equip-
ment;
– replacement parts may not be available or very
difficult to get.
Porsche cannot be responsible for the me-
chanical damage that could result because
of inadequate fuel, service or parts availabi-
lity.
If you purchased your Porsche abroad and want to
bring it back home, be sure to find out about ship-
ping and forwarding requirements, as well as cur-
rent import and customs regulations.

194
Maintenance, Car Care Automatic car washes
Optional add-on parts or parts which project
beyond the contours of the vehicle may be
damaged by design features (e.g. brushes) of au-
tomatic car washes.
The following parts are particularly suscep-
tible to damage:
– Convertible top (hot wax treatment cannot be
used, as the wax attacks the convertible top
material),
– Windshield wipers (always switch them off to
prevent them wiping unintentionally in intermit-
tent or sensor operation)
– External telephone antenna (always unscrew)
– Fixed rear spoiler or extended rear spoiler
– Wheels (the wider the rim and the lower the tire
height, the greater the risk of damage)
– High-gloss wheels (to prevent these from get-
ting scratched, do not clean with the wheel-
cleaning brushes of the car wash).
fPlease consult the operator before using auto-
matic car washes.
fWash and dry by hand all points not reached by
a car wash, such as door and lid seams or
door sills. Note
Automatic car washes spray water at odd angles
and high pressures, which are not seen in normal
driving. Therefore, water can sometimes find its
way into the passengers compartment during or
shortly after the car wash.
Door locks fTo prevent the door locks from freezing during
the cold season, the lock cylinders should be
covered during a wash.
fShould the locks freeze, use an ordinary de-
icer. In many cases, a well warmed key can
help.
Never use excessive force.

200
Maintenance, Car Care
Storing your Porsche If you intend to store your Porsche for a prolonged
period, please consult your authorized Porsche
dealer. The staff will be glad to advise you on the
most suitable and necessary methods.
fClean your vehicle thoroughly inside and out-
side.
Clean the engine compartment.
The under carriage and chassis components
should be free of dirt and salt deposits.
fFill up the fuel tank.
fChange the oil and oil filter, and run the engine
for several minutes.
fIncrease the tire pressure to 58 psi (4 bar).
It is not recommended to lift the vehicle, due to
the possibility of corrosion on shock absorber
piston shafts.
The vehicle should be moved slightly, approxi-
mately every four weeks, to prevent flat spot
on the tires. Climate control
The air conditioning system should be in good wor-
king condition and fully charged.
Windshield/Headlight washer
fCheck and correct antifreeze/cleaning solution
level as necessary.
Electrical system
fRemove the battery from the vehicle and store
it in a cool dry place, not on a cement floor.
When the battery is disconnected, the
alarm system is deactivated.
fRecharge the battery every 3 months. If the
battery remains in the vehicle with the cables
connected, it is necessary to check, remove
and recharge the battery every 2-3 weeks.
Do not fast charge the battery.
fPlease observe the chapter “BULB CHART” on
Page 239. Vehicle interior
The interior must be dry, especially in the area of
the floor carpets. The use of drying agents (Silica-
Gel) is recommended in vehicles with leather inte-
rior and in areas with high humidity. The recom-
mended amount is 3 fabric bags of 1.1 lbs. (500
grams) each placed on the floor carpets.
Windows, doors, lids and top must be closed. The
air vents should be opened.

206
Practical Tips, Emergency Service
Tire pressures
Warning!
Incorrect tire pressure causes increased tire
wear and adversely affects road handling.
fAlways use an accurate tire pressure gauge
when checking inflation pressures.
fDo not exceed the maximum tire pressure list-
ed on the tire sidewall.
Please observe the chapter “VEHICLE IDENTI-
FICATION NUMBER” on Page 258.
fCold tire inflation pressure means: all tires
must be cold, ambient temperature maximum
(68°F, (20°C)
, when adjusting the inflation pres-
sure.
Avoid sunlight striking the tires before measur-
ing cold pressures, since the pressures would
rise from temperature influence.
fValve caps protect the valve from dust and dirt,
and thus from leakage.
Always screw caps tightly down.
Replace missing caps immediately.
fUse only plastic valve caps.
fDo not use commercially available sealant or
tire inflating bottles. Only use Porsche approved tire sealant.The tire pressure must match the prescribed val-
ue.
You can find information on tire pressure:
– on Page 5 of this Owner’s Manual
– and in the left door aperture.
These values are for cold tires (68°F (20 °C)).
fCheck the tire pressure at least every
2 weeks. Always check when tires are cold.
When tires are warm, the tire pressure is
increased.
fNever let air out of hot tires.
This could cause the tire pressure to fall below
the prescribed value.
Insufficient tire filling pressure can cause tires to
overheat and thus be damaged – even invisibly.
Hidden tire damage is not eliminated by subse-
quently correcting the tire pressure.Overloading
Danger!
Risk of personal injury, loss of control and
damage to vehicle parts.
fDo not overload your vehicle. Be careful about
the roof load.
fIf loading the vehicle also correct the tire pres-
sure. Tire pressure for loaded vehicle can be
found on the tire pressure plate and in the
chapter technical data.
fNever exceed the specified axle load.
Overloading can shorten the service life of the
tires and car, as well as lead to dangerous ve-
hicle reactions and long braking distances.
Damage due to overloading is not covered by the vehicle warranty.
fPlease observe the chapter “LOADING INFOR-
MATION” on Page 216.
fPlease observe the chapter “TIRE PRESSURE
FOR COLD TIRES” on Page 264.

Practical Tips, Emergency Service
207
Example of a tire pressure plate ATire pressure plateDepending on when your vehicle was manufac-
tured, the tire pressure plate in the left door aper-
ture will contain different data.
Information on the tire pressure plate A
A Seating capacity
Maximum number of vehicle occupants, includ-
ing the driver.B Vehicle load limit
Is the maximum total weight limit specified of
the load (passengers and cargo) for the vehi-
cle. This is the maximum weight of passengers
and cargo that can be loaded into the vehicle.
If a trailer is being towed, the trailer tongue
weight must be included as part of the cargo
load.
Please observe the chapter “LOADING INFOR-
MATION” on Page 216.
C Tire size for the front axle
Check with your authorized Porsche dealer
about the current release status.
D Recommended tire pressure for the front axle
These values are for cold tires (68°F/20 °C).
E Tire size for the rear axle
Check with your authorized Porsche dealer
about the current release status.
F Recommended tire pressure for the rear axle
These values are for cold tires (68°F/20 °C).
G In vehicles with collapsible spare wheel:
Size and tire pressure of the spare wheel.
Example of a tire pressure plate BInformation on the tire pressure plate B
A Information for tire sealant, seating capacity,
vehicle load limit
B Approved tire size for the front axle
C Permissible tire pressure for the front axle
D Tire pressure for fully loaded or partially
loaded vehicle
E Permissible tire pressure for the rear axle
F Approved tire size for the rear axle

208
Practical Tips, Emergency Service
Tire traction
Warning!
When driving on wet or slushy roads, a
wedge of water may build up between the
tires and the road. This phenomenon is
known as “hydroplane” and may cause par-
tial or complete loss of traction, vehicle
control or stopping ability.
fReduce speed on wet surface to prevent this. Tire life Tire life depends on various factors, i. e., road
surfaces, traffic and weather conditions, driving
habits, type of tires and tire care.
fInspect your tires for wear and damage before
driving off. If you notice uneven or substantial
wear, wheels might need alignment or tires
should be balanced or replaced.
Tire wear The original equipment tires on your Porsche have
built-in tire wear indicators. They are molded into
the bottom of the tread grooves and will appear as
approximately 1/2 in. (12 mm) bands when the
tire tread depth is down to 1/16 of an in.
(1.6 mm).
When the indicators appear in two or more adja-
cent grooves, it is time to replace the tires. We
recommend, however, that you do not let the tires
wear down to this extent.
Worn tires cannot grip the road surface properly
and are even less effective on wet roads.
In the United States, state laws may govern the
minimum tread depth permissible. Follow all such
laws.
Danger!
Driving on worn tires can result in loss of con-
trol of the vehicle and could cause serious
personal injuries or death.
fDo not drive with worn tires or tires showing
cuts or bruises as they may lead to sudden
deflation and loss of control which could cause
severe personal injury.
fSpecialized high performance tires on high
performance sports cars exhibit more wear
than those on a family sedan, or even a high
performance sedan.
Therefore, it is important to check your tire
pressure and condition at least every two weeks.
If you notice that tires are wearing unevenly, con-
sult your Porsche dealer.
Uneven wear may not always be due to improper
wheel alignment. It can be the result of individual
driving habits such as cornering at high speeds. If
the tire pressure is not checked and adjusted
regularly, abnormal tire wear can also occur.

Practical Tips, Emergency Service
209
Tire care fAvoid damaging tires and wheel rims.
fIf you must drive over a curb or other obstacle,
drive slowly and at an obtuse angle.
fCheck tires for uneven wear and damage
before driving off.
fRemove imbedded material.
fReplace worn or damaged tires immediately.
fKeep oil, fuel, brake fluid, etc. away from tires.
fReplace missing valve stem caps.
fKeep tires inflated correctly.
fWash tires when washing the vehicle.
Also clean inner side of wheels.
fDo not use abrasive cleaners when washing
the wheels.
fCheck wheel rims for corrosion.
fRemove road salt, if driving in winter.
Tire damage, puncture fCheck tires for imbedded material, cuts, punc-
tures, cracks and bulges (side wall) before driv-
ing off.
In case of tire damage, where it is uncertain wheth-
er there is a break in the ply with all its conse-
quences or tire damage caused by thermal or me-
chanical overloading due to loss of pressure or
any other prior damage, we recommend that the
tire be replaced for safety reasons.
If one faulty tire is replaced it should be noted that
the difference in tread depth on one axle must not
exceed 30 %.
Handling inconsistencies may result.
fPerform a visual inspection if necessary.
Danger!
Risk of serious personal injury or death.
Driving the vehicle with low tire pressure
increases risk of a tire failure and resulting
loss of control. Furthermore, low tire pres-
sure increases rate of wear of the affected
tires.
fCheck tires – including sidewalls – regularly for
foreign bodies, nicks, cuts, cracks and bulges.
fAfter driving off road, examine tires for signs
of damage such as cuts, tears, bulges or for-
eign objects stuck in the tread. Replace a dam-
aged tire if necessary.
fCross curb edges slowly and at right angles if
possible.
Avoid driving over steep or sharp curbs.
fIn cases of doubt, have the wheel (particularly
the inner side) checked by an authorized Porsche dealer.

Practical Tips, Emergency Service
211
Wheel alignment, wheel balancing As a precaution, have wheels with summer tires
balanced in the spring, and those with mud and
snow tires before winter.
Unbalanced wheels may affect car handling and
tire life.
Only the specified weights may be used for wheel
balancing.
Self-adhesive weights must not come into contact
with cleaning agents, since they could drop off.
Uneven tread wear indicates wheel imbalance. In
this event, the vehicle should be checked at an au-
thorized Porsche dealer.
Warning!
If, during a journey, uneven running or vibra-
tions occur that could be caused by damage
to tires or the car, the speed must be re-
duced immediately, but without braking
sharply.
If you continue your trip without having the
cause of the fault remedied, you might lose
control of your vehicle which could cause se-
vere personal injury.
fStop the vehicle and check the tires.
fIf no cause for the fault can be found, drive
carefully to the nearest authorized Porsche dealer.
Removing and storing tires fAfter changing, adjust tire pressure and torque
wheel bolts diagonally to 94 ftlb (130 Nm).
Tires must always remain on the same side of
the vehicle.
When wheels are removed, the direction of
rotation and position of each wheel should be
marked.
Example
FR (front right), FL, RR and RL.
Wheels must always be fitted in accordance with
their marking.
The preception that tire durability and perform-
ance are immune to the effects of storage and
age is unfounded.
Chemical additives, which make the rubber elas-
tic, lose their effectiveness in the course of time
and the rubber becomes brittle and cracks.
Therefore, the tires should be inspected from
time to time. Note
Under no circumstances should tires older than 6
years be used on your Porsche.
The age of the tire can be obtained from the “DOT”
code number. If, for example, the last four num-
bers read 1204, then the tire was produced in the
12th week of 2004.
fStore tires in a cool and dry place.