2004 PORSCHE 911 GT3 engine

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.

Power Steering
Power steering isassisted byhydraulic auxiliary
forces.
The hydraulic fluidreservoir islocated inthe en-
gine compartment.

Note

The flow noise heard atfull steering lockisdesign-
related anddoes notindicate adefect inthe steer-
ing syste m.
A

Warning!
Risk ofaccident.
When theengine isstopped
(e.g.
when on
tow) orthe hydraulic systemfails,there isno
assistance forsteering.
Therefore, substantially moreforce willhave
to be exerted inorder tosteer.

I>
Exercise greatcarewhen being towed.

t>
Have thefault remedied atyour nearest autho·
rized Porsche dealer.
Checking
hydraulicfluid

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

I>
Only usehydraulic fluidauthorized byPorsche.
Specification:
Please observe thechapter "CAPACITIES" on
Page 185.
Check thefluid level withtheengine stopped and

cold
(approximately 68°F
j20°C).

1. Start theengine andletitidle forapprox.
20 seconds.
Switch offthe engine.
2. Open theengine compartment lid.
3. Open thereservoir cap.
4. Wipe measuring rod.
Close lidand reopen. Thefluid level should lie
in the area ofthe "Cold" marking.
Add hydraulic fluidifnecessary.
5. Close capcarefully.
Close engine compartment lid.
Noticeable lossoffluid indicates leakageinthe
system.
The cause should beremedied immediately atan
authorized Porschedealer.
Maintenance, CarCare
J.27

AirFilter

A dirty airfilter notonly reduces engineperfor-
mance, butcan lead topremature enginewear.
Regular filterreplacement ispart ofthe routine
maintenance service.

[>
Industy conditions, checkthefilter element
more frequently andreplace ifnecessary.

Particle Filter

The fresh airpassing through theparticle filterinto
the passenger compartment isvirtually freeof
dust andpollen.

[>
Ifthe outside airispolluted byexhaust fumes,
press thecirculating-air button.
A dirty filter canbethe cause ofreduced airflow:

[>
Have filterreplaced byyour authorized
Porsche dealer.
Regular filterreplacement ispart ofthe routine
maintenance service.
Maintenance, CarCare
Manual
Transmission Oil

The transmission oilhas tobe checked and
changed atthe intervals listedinyour Maintenance
Schedule.

[>
Please observe thechapter "CAPACITIES" on
Page 185.
We recommend thatyouhave thetransmission oil
changed atyour Porsche dealer,whohasthere-
quired lubricants andthenecessary fillingequip-
ment.
If you suspect anoilleak inthe transmission, have
your authorized Porschedealercheckitout imme-
diately.

Engine compartment

The engine compartment andthesurface ofthe
engine aretreated withacorrosion-inhibitor atthe
factory.
If degreasing solventsareused toclean theen-
gine compartment orthe engine iswashed down,
the process almostinvariably removesthecorro-
sion-inhibiting coating.Itis then absolutely neces-
sary tohave adurable preservative appliedtoall
surfaces, bodyseams, jointsandassemblies in
the engine compartment. Thisalsoapplies when
corrosion-inhibitor partsarereplaced.

/!\
Caution!

Risk ofdamage tothe generator.

c>
Donot point thecleaning jetdirectly atthe al-
ternator, orcover thealternator.
Effective corrosion-proofing isparticularly impor-
tant during thecold weather season.Ifyour caris
driven frequently inareas where salthasbeen
spread onthe roads, thewhole engine compart-
ment should becleaned thoroughly afterthewin-
ter toprevent saltfrom causing anylasting dam-
age. Afull under-body washshould alsobeper-
formed atthe same time.
Windows

The road dustwhich settles onthe windshield and
windows containsparticles oftire rubber andoil
residue. Theinterior trimandupholstery release
particles, particularly instrong sunlight, whichcol-
lect onthe insides ofthe windows. Thesedeposits
are augmented byimpurities inthe airwhich en-
ters thecarthrough thefresh airvents.

c>
Clean allwindows regularly, insideandoutside,
with Porsche windowcleaner.

c>
Ifyou useachamois leatherforthe windows,
do not use itfor paintwork asitwill otherwise
pick upacertain amount ofpreservative orpol-
ish and could smear tilewindows andthus im-
pair vision.

c>
Remove deadinsects withthePorsche insect
remover.

Wiper blades

Wiper blades thatareinperfekt condition arevital
for aclear view.

c>
Replace thewiper blades twiceperyear (be-
fore andafter thecold season) orwhenever
wiper performance deteriorates.
C>

Periodically cleanthewiper blades with
Porsche windowcleaner, especially afterthe
vehicle hasbeen washed inacar wash.
If they arevery dirty (e.g. withinsect remains),
they canbecleaned withasponge orcloth.

Undercoating

As itis not possible toexclude therisk ofdamage
to this protective coatinginday today driving, it
is advisable tohave theunderside ofthe car in-
spected atcertain intervals -preferably beforethe
start ofwinter andagain inspring -and theunder-
coating restored asnecessary.
Your authorized Porschedealerisfamiliar withthe
bodyseal treatment procedures andhasthenec-
essary equipment forapplying factoryapproved
materials. Werecommend thatyouentrust them
with such work andinspections.
Unlike conventional sprayoils,undercoating and
rust-proofing compoundsbasedonbitumen or
wax donot attack thesound-proofing materialsap-
plied atthe factory.
Maintenance, CarCare
133

A
Warning!
Danger offire and serious personal injuries.

t>
Donot apply additional undercoating orrust-
proofing onornear theexhaust manifold, ex-
haust pipes, catalytic converters orheat
shields. Duringdriving thesubstance usedfor
undercoating couldoverheat andignite.

t>
Before applying freshunderseal, carefullyre-
move deposits ordirt and grease. Onceithas
dried, thenew undercoating compoundforms
a tough protective coatingwhichprovides effi-
cient rust-proofing ofthe floor panels andcom-
ponents.

t>
Always applyafresh coating ofsuitable preser-
vative tounprotected areasaftercleaning the
underside ofthe body, thetransmission, the
engine orcarrying outrepairs tounder-body,
engine ortransmission components.
Effective rust-proofing isparticularly important
during thecold weather season.
If
your carisdriv-
en frequently inareas where salthas been spread
on the roads, thewhole engine compartment
should becleaned thoroughly afterthewinter to
prevent saltfrom causing anylasting damage. A
full under-body washshould alsobeperformed at
the same time.

134
Maintenance, CarCare
Door,
roof,lidand window seals

t>
Wash dirt(e.g. abrasion, dust,roadsalts) from
all seals regularly usingwarm soapy water. Do
not use anychemical cleaningagentsorsol-
vents.
When thereisafrost hazard, theouter doorseals
and thefront andrear lidseals canbeprotected
against freezing intoplace byasuitable careprod-
uct.

In order toprevent damage tothe anti-
friction coating, theinner doorseals must
not betreated withcare products.
Headlights,
lights,interior andexterior

plastic parts

t>
Use
only
clean water andalittle dishwashing
detergent toclean lightlenses, plastichead-
light lenses, plasticpartsandsurfaces.
Do not clean whendry.
Use asoft sponge orasoft, lint-free cloth.Gen-
tly wipe thesurface withoutapplying toomuch
pressure.
The Porsche insidewindow cleanerisalso suit-
able forcleaning plasticsurfaces. Followthe
cleaning instructions onthe container.
Never useother chemical cleanersor
solvents.

£>
Rinse cleaned surfaces withclear water.