fuel PORSCHE 911 GT3 2004 5.G Owner's Guide

Octane ratings

The CLC orAKI octane ratingisusually lowerthan
the RON rating:
For example: 95RON equals 90CLC orAKI
Unleaded
fuelsmaynotbeavailable outsidethe
continental U.S.andCanada. Therefore, werec-
ommend youdonot take your cartoareas or
countries whereunleaded fuelmay notbeavail-
able.
Octane ratingindicates afuel's ability toresist det-
onation. Therefore, buyingthecorrect octanegas
is important toprevent engine"damage".
The RON octane ratingisbased onthe research
method. TheCLC (U.S. CostofLiving Council oc-
tane rating) orAKI (antiknock index)octane rating
usually displayed onU.S. fuelpumps iscalculated
as research octanenumber plusmotor octane
number, dividedby2,that iswritten as:
Fuels
containing MMT

Some NorthAmerican fuelscontain anoctane en-
hancing additive calledmethylcyclopentadienyl
manganese tricarbonyl(MMT).

If
such fuels areused, youremission controlsys-
tem performance maybenegatively affected.
The check engine warning lightonyour instrument
panel mayturnon.

If
this occurs, Porsche recommends youstop us-
ing fuels containing MMT.
Portable FuelContainers

/!\
Danger!
Portable fuelcontainers, fullorpartially
empty, mayleakcausing anexplosion, orre-
sult infire incase ofan accident.

D>
Never carryadditional fuelinportable contain-
ers inyour vehicle.

Fuels
containing alcoholandether

Some areasofthe U.S. require oxygenated fuels
during certain portions ofthe year. Oxygenated fu-
els are fuels which contain alcohols (suchasmeth-
anol orethanol) orether (such asMTBE).
Under normal conditions, theamount ofthese
compounds inthe fuel willnot affect driveability.
You may useoxygenated fuelsinyour Porsche,
provided theoctane requirements foryour vehicle
are met. Werecommend, however,tochange to
a different fuelorstation
if
any ofthe following
problems occurwithyour vehicle:
- Deterioration ofdriveability andperformance.
- Substantially reducedfueleconomy.
- Vapor lockandnon-start problems, especially
at high altitude orathigh temperature.
- Engine malfunction orstalling.
R+M

-2-

or

RON+MON

2

Maintenance,CarCare
123

Emission ControlSystem

In the interest ofclean air
Pollution ofour environment hasbecome aprob-
lem that isof increasing concerntoall ofus. We
urge youtojoin us
in
our efforts forcleaner airin
controlling thepollutants emittedfromtheauto-
mobile.
Porsche hasdeveloped anemission controlsys-
tem that controls orreduces thosepartsofthe
emission thatcanbeharmful toour environment.
Your Porsche isequipped withsuch asystem.
Porsche warrants theEmission ControlSystem in
your newcarunder theterms andconditions set
forth inthe Warranty Booklet.
You, asthe owner ofthe vehicle, havethe
responsibility toprovide regularmaintenance ser-
vice forthe vehicle andtokeep arecord ofall
maintenance workperformed. Tofacilitate record
keeping, havetheservice performed byautho-
rized Porsche dealers.TheyhavePorsche trained
technicians andspecial toolstoprovide fastand
efficient service.
Maintenance, CarCare
To
assure efficient operation ofthe Emission
Control System:

~ Have yourvehicle maintained properlyandin
accordance withtherecommendations de-
scribed inyour Maintenance Booklet.
Lack ofproper maintenance, aswell asim-
proper useofthe vehicle, willimpair thefunc-
tion ofthe emission controlsystem andcould
lead todamage.
~ Donot alter orremove anycomponent ofthe
emission controlsystem.
~ Donot alter orremove anydevice, suchas
heat shields, switches, ignitionwires,valves,
etc., which aredesigned toprotect yourvehi-
cle's emission controlsystem.
In addition toserious enginedamage, thiscan
result inafire
if
excess rawfuel reaches the
exhaust system.
~ Donot continue tooperate yourvehicle ifyou
detect engine misfireorother unusual operat-
ing conditions. Parking

A
Warning!
Danger offire.

~ Donot park oroperate thevehicle inareas
where thehotexhaust systemmaycome in
contact withdrygrass, brush,fuelspill oroth-
er flammable material.

~ If
your carcatches onfire forany reason, call
the fire department.
Do not endanger yourlifebyattempting toput
out the fire.
Undercoating

A
Warning!
Danger offire and serious personal injuries.

~ Donot apply additional undercoating orrust-
proofing onornear theexhaust manifold,
exhaust pipes,catalytic converters orheat
shields. Duringdriving thesubstance usedfor
undercoating couldoverheat andignite.

HowEmission ControlWorks

When anautomobile engineisrunning, ituses en-
ergy generated throughthecombustion ofamix-
ture ofair and fuel. Depending onwhether acar is
driven fastorslowly orwhether theengine iscold
or hot, some ofthe fuel (hydrocarbons) maynot
be burned completely, butmay bedischarged into
the engine crankcase orexhaust system.Additon-
al hydrocarbons mayenter theatmosphere
through evaporation offuel from thefuel tank.
These hydrocarbons
(He),
when released intothe
air, contribute toundesirable pollution.
In addition, carbonmonoxide (CO)andoxides of
nitrogen (NOx)contribute toengine emissions.
They, too,areformed duringthecombustion pro-
cess anddischarged intotheexhaust system.
To reduce thesepollutants, yourPorsche is
equipped withaprecisely calibrated fuelinjection
system toassure afinely balanced air/fuelmixture
under alloperating conditions.
Oxygen
sensor

The oxygen sensor, installed inthe exhaust pipe
continuously sensestheoxygen content ofthe
exhaust andsignals theinformation toan electron-
ic control unit.Thecontrol unitcorrects theair/
fuel ratio, sothe engine always receives anaccu-
rately metered air/fuelmixture.

Crankcase ventilation

Through crankcase ventilation, undesirable emis-
sions fromtheengine crankcase arenotpermit-
ted toreach theoutside atmosphere. Theseemis-
sions arerecirculated fromthecrankcase tothe
air intake system. Fromheretheemissions mix
with theintake airand arelater burned inthe en-
gine.

Catalytic converters

The catalytic converters areefficient "clean-up"
devices builtintotheexhaust systemofthe vehi-
cle. The catalytic converters burntheundesirable
pollutants inthe exhaust gasbefore itis released
into theatmosphere.

The exclusive useofunleaded fueliscritical-
ly important forthe lifeofthe catalytic con-
verters. Therefore, onlyunleaded fuelmust
be used. The
catalytic converters willbedamaged by:

- push ortow starting thevehicle
- misfiring ofthe engine
- turning offthe ignition whilethevehicle ismov-
ing or
- driving untilthefuel tank iscompletely empty
- byother unusual operating conditions.

t>
Donot continue tooperate yourvehicle under
these conditions, sincerawfuelmight reach
the catalytic converters. Thiscould result in
overheating ofthe converters. Federallawpro-
hibits useofleaded fuelinthis car.
Maintenance, CarCare
125

FuelEvaporation Control

Fuel tank venting
The evaporation chamberandthecarbon canister
prevent fuelfrom escaping tothe atmosphere at
extreme highoutside temperatures, whendriving
abruptly aroundcurvesandwhen thecar isparked
at an incline orinany other nonlevel position.
Vapor control systemandstorage
When thefuel tank isfilled, vapors arecollected in
the evaporation chamberbyavent lineleading the
vapors tothe carbon canister wheretheyare
stored aslong asthe engine doesnotrun.
Purge system
When theengine isrunning, thefuel vapors from
the canister willbemixed withfresh airfrom the
ambient airofthe canister. Thismixture willbe
directed tothe intake airhousing bythe tank vent
line, mixed withtheintake airand burned during
normal combustion.
Maintenance, CarCare
Washer
Fluid

The reservoir, withablue screw cap,isinthe lug-
gage compartment, tothe rear left.
Capacity
- Without headlight cleaningsystem:
approximately 3.2quarts (3liters).
- With headlight cleaningsystem:
approximately 6.1quarts (5.7liters). Clean
water isgenerally notenough toclean the
windshield andheadlights.
It is advantageous toadd awinter cleaner giving
antifreeze protection orasuitable summer clean-
er, depending onthe season. Followtheinstruc-
tions forthe mixing ratio.

\>
Donot use engine coolant anti-freeze orany
other solution thatcandamage thecar's paint,
in the washer reservoir.

\>
Please noteallthe information onthe container
of the cleaning agent.

e
Warning light
The warning lightsinthe instrument panelandon-
board computer lightwhen approximately 0.5liter
(0.52 quarts) isleft inthe reservoir.

CarCare Instructions

I>
Please observe thechapter "EXERCISE EX-
TREME CAUTION WHENWORKING ONYOUR
VEHICLE" onPage 112.

Regular andcorrect carehelps tomaintain
the value ofyour carand isalso a
precondition forthe New Vehicle Warranty
and theAnti Corrosion Warranty.
Your authorized Porschedealerhas
specially developed car-careproductsfrom
the Porsche program available eithersingly
or as complete car-caresets.They willbe
pleased tohelp youselect suitable products.
Whether youusePorsche products orother
commercially availablecleaningagentsfirst
make sureoftheir correct application.

A Porsche thatiswell-cared forcan look likenew
for years.
It
all depends onthe amount ofcare the
owner iswilling togive thecar.

130
Maintenance, CarCare
A

Warning!
Risk ofserious personal injuryordamage to
the vehicle orproperty.
Cleaning agentsmaybehazardous toyour
health.
Most chemical cleanersareconcentrates
which require dilution. Highconcentrations
might cause problems rangingfromirritation
to serious injuryaswell asdamage toyour
vehicle.

t>
Keep cleaning agentsoutofreach fromchil-
dren.

I>
Observe allcaution labels.

I>
Always readdirections onthe container before
using anyproduct. Thesedirections maycon-
tain information necessarytoavoid personal
injury.

t>
Donot use fuel, kerosene, naphtha,nailpolish
remover orother volatile cleaning fluids.They
may betoxic, flammable orhazardous inother
ways. Onlyusespot removing fluidsinawell
vented area.

I>
Donot clean theunderside ofchassis, fend-
ers, wheel covers, etc.,without protecting
your hands andarms asyou may cutyourself
on sharp-edged metalparts. Moisture
androad saltonbrakes mayaffect brak-
ing efficiency.

I>
Test thebrakes aftereach vehicle washing.

Storing yourPorsche

If you intend tostore yourPorsche foraprolonged
period, pleaseconsult yourauthorized Porsche
dealer. Thestaff willbeglad toadvise youonthe
most suitable andnecessary methods.
r> Clean yourvehicle thoroughly insideandout-
side.
Clean theengine compartment.
The under carriage andchassis components
should befree ofdirt and saltdeposits.
r> Fillupthe fuel tank.
r> Change theoiland oilfilter, andrunthe engine
for several minutes.
r>

Increase thetire pressure to58 psi (4bar).
It is not recommended tolift the vehicle, dueto
the possibility ofcorrosion onshock absorber
piston shafts.
The vehicle shouldbemoved slightly, approxi-
mately everyfourweeks, toprevent flatspot
on the tires.

Climate control

The airconditioning systemshouldbeingood
working condition andfully charged.

WindshieldjHeadlight washer

r> Check andcorrect antifreeze/cleaning solu-
tion level asnecessary.

Electrical system

r> Remove thebattery fromthevehicle andstore
it in acool dryplace, notonacement floor.

When thebattery isdisconnected, the
alarm system isdeactivated.

r> Recharge thebattery every3months. Ifthe
battery remains inthe vehicle withthecables
connected, itis necessary tocheck, remove
and recharge thebattery every2-3weeks.

Do not fast charge thebattery.

r> Please observe thechapter "SATTERY" on
Page 155.
Vehicle
interior

The interior mustbedry, especially inthe area of
the floor carpets. Theuseofdrying agents (Silica-
Gel) isrecommended invehicles withleather inte-
rior and inareas withhighhumidity. Therecom-
mended amountis3fabric bagsof1.1 Ibs.
(500 grams) eachplaced onthe floor carpets.
Windows, doorsandlidsmust beclosed. Theair
flaps should beopened.
Maintenance, CarCare

Exercise ExtremeCautionwhen
Working onyour Vehicle

A
Warning!
Ignoring thefollowing instructions may
cause serious personal injury.

I>
The engine compartment ofany motor vehicle
is apotentially hazardous area.Ifyou arenot
fully familiar withproper repairprocedures, do
not attempt theadjustments describedonthe
following pages.
This caution appliestothe entire vehicle.

I>
Only work onyour vehicle outdoors orinawell
ventilated area.

I>
Ensure thatthere arenoopen flames inthe
area ofyour vehicle atany time when fuel
fumes mightbepresent. Beespecially cau-
tious ofsuch devices suchashot water heat-
ers which igniteaflame intermittently.

I>
Before working onany part inthe engine com-
partment, turntheengine offand letitcool
down sufficiently. Hotengine compartment
components canburn skinoncontact.

I>
Bealert andcautious aroundengineatall
times whiletheengine isrunning.
If work hastobe performed withtheengine
running, alwayssetthe parking brake,and
make suretheshift lever isin neutral position.

140
PracticalTips,Emergency Service
I>

Inparticular, bevery careful toensure that
items ofclothing (ties,shirt, sleeves etc.),jew-
elry, long hair,hand orfingers cannotget
caught inthe engine-compartment blower,fan,
belts orother moving parts.
The radiator andradiator fansareinthe front
of the car.
The fans canstart orcontinue runningasa
function oftemperature, evenwiththeengine
switched off.
Carry outwork inthese areasonlywith theen-
gine off,theignition switched off,and exercise
extreme caution.

I>
Your Porsche isequipped withanelectronic ig-
nition system. Whentheignition ison, high volt-
age ispresent inall wires connected withthe
ignition system; therefore, exerciseextreme
caution whenworking onany part ofthe engine
while theignition ison orthe engine isrunning.

I>
Always support yourcarwith safety stands ifit
is necessary towork under thecar.

I>
When working underthecarwithout safety
stands butwith thewheels onthe ground,
make surethecar ison level ground, the
wheels areblocked, andthat theengine
cannot bestarted.
Remove theignition key.
I>

Donot smoke orallow anopen flame around
the battery orfuel.
Keep afire extinguisher inclose reach.

I>
Incomplete orimproper servicingmaycause
problems inthe operation ofthe car. Ifin doubt
about anyservicing, haveitdone byyour au-
thorized Porschedealer.
Improper maintenance duringthewarranty pe-
riod may affect yourPorsche warranty cover·
age.

I>
Supplies offluids, e.g.engine oil,brake fluidor
coolant, arehazardous toyour health.
Keep these fluidsoutofchildren's reachand
dispose ofthem inaccordance withtheappro-
priate regulations.

I>
Some countries requireadditional toolsand
special sparepartstobe carried.
Please makeenquiries beforedriving abroad.

Tirewear

The original equipment tiresonyour Porsche have
built-in tirewear indicators. Theyaremolded into
the bottom ofthe tread grooves andwillappear as
approximately 1/2in(12 mm) bands whenthetire
tread depth isdown to1/16 ofan in(1.6 mm).
When theindicators appearintwo ormore adja-
cent grooves, itis time toreplace thetires. We
recommend, however,thatyoudonot letthe tires
wear down tothis extent.
Worn tirescannot griptheroad surface properly
and areeven lesseffective onwet roads.
In the United States, statelawsmaygovern the
minimum treaddepth permissible. Followallsuch
laws.
PracticalTips,Emergency Service
/!\

Warning!
Driving onworn tirescanresult inloss of
control ofthe vehicle andcould cause severe
personal injuries.

0>
Donot drive withworn tiresortires showing
cuts orbruises asthey mayleadtosudden
deflation andloss ofcontrol whichcouldcause
severe personal injury.

0>
Specialized highperformance tiresonhigh
performance sportscarsexhibit morewear
than those onafamily sedan, oreven ahigh
performance sedan.
Therefore, itis important tocheck yourtire
pressure andcondition atleast every two
weeks.
If you notice thattires arewearing unevenly, con-
sult your Porsche dealer.
Uneven wearmaynotalways bedue toimproper
wheel alignment. Itcan bethe result ofindividual
driving habitssuchascornering athigh speeds. If
the tire pressure isnot checked andadjusted
regularly, abnormal tirewear canalso occur.
Tire
care

0>
Avoid damaging tiresandwheel rims.

0>
Ifyou must driveoveracurb orother obstacle,
drive slowly andatan obtuse angle.

0>
Check tiresforuneven wearanddamage
before driving off.

0>
Remove imbedded material.

0>
Replace wornordamaged tiresimmediately.

0>
Keep oil,fuel, brake fluid,etc.away fromtires.

0>
Replace missingvalvestemcaps.

0>
Keep tiresinflated correctly.

Adjusting Headlights

c>
Please observe thechapter "LIGHTS, REPLAC-
ING BULBS" onPage 162.
Adjustment
The adjustment ismade withthevehicle readyto
drive andthefuel tank completely filled.
The driver's seatmust beloaded byaperson ora
165 Ibs.(75kg)weight andthetire pressures
must meet theprescribed values.
After being loaded, thecarmust berolled afew
meters sothat thesuspension cansettle. For
checking theheadlight adjustment, theverti-
cal position ofthe cutoff ofthe lowbeam (seefig.)
has tobe projected onavertical screen(wall)in
distance of7.5 mfrom thefront lensofthe head-
lamp.
The correct position ofthe cutoff is5cm at7.5 m
(0.4°) below ahorizontal line,xcm from ground to
the center ofthe headlamp lens. Lateral
adjustment ofthe headlights shouldbe
carried outataspecialist workshop withanoptical
adjustment unit.

Distance

Visual aimshall beperformed atnot less than
7.5 m(this value isarounded downconversion
from the25-foot distance typicaloffield aimusing
a screen). The7.5mdistance ismeasured from
the headlamp lenstothe viewing screen.

c> c>c>

Practical Tips,Emergency Service
175

CapacitiesUse only fluids andfuels authorized byPorsche. Yourauthorized Porschedealerwillgladly advise you.

Your Porsche hasbeen designed sothat itis not necessary tomix anyadditives withoilsorfuels.
Engine
CoolantManual transmission
and differential
Fuel tank
Fuel quality
Power steering
Brake fluid
Windshield washer
Oil
change quantity withoutoilfilter approx. 9.3quarts/S.75 liters
Oil change quantity withoilfilter approx. 9.6quarts/9.0 liters
Reference indicationisthe level onthe oildipstick.
Please observe thechapter "ENGINE Oil"onPage 114.
approx. 7.39U.S.gallons/28 liters
3.5 quarts/3.3 literstransmission oilSAE 75W-90, Mobilube PTX
approx. 16.6U.S.gallons/63 liters
Your engine isdesigned toprovide optimum performance andfuel economy using

unleaded premiumfuelwith anoctane ratingof98 RON (93CLC orAKI).

Porsche therefore recommends theuse ofthese fuelsinyour vehicle.
Porsche alsorecognizes thatthese fuelsmaynotalways beavailable. Beassured thatyour vehicle
will operate properly onunleaded premiumfuelswithoctane numbers ofatleast
95RON (90CLC orAKI),

since theengine's "Electronic Oktane
™
knock control" willadapt theignition timing,ifnecessary.
approx. 1.35quarts/1.27 literhydraulic fluidPentosin CHF11S®
0.67 quarts/0.63 liters;useonly Original Porsche brakefluid.
approx. 3.19quarts/3 literswithout headlight washer
approx. 6.06quarts/5.7 literswithheadlight washer
TechnicalData