2004 PORSCHE 911 GT3 Owners Manual

FuelEconomy

Fuel economy willvary depending onwhere,
when andhow youdrive, optional equipment
installed, andthegeneral condition ofyour
car.
A car tuned tospecifications andcorrectly
maintained, willhelp youtoachieve optimal
fuel economy.

~ Have yourvehicle tunedtospecifications.
Air cleaner shouldbedirt free toallow proper
engine "breathing".
Battery shouldbefully charged.
Wheels shouldbeproperly aligned.
Tires should beinflated atcorrect pressure.
~ Always monitor yourfuelconsumption.
~ Drive smoothly, avoidabrupt changes inspeed
as much aspossible.
~ Avoid jackrabbit startsandsudden stops.
~ Donot drive longer thannecessary inthe lower
gears. Shifting intoahigher gearearly without
lugging theengine willhelp save fuel.
~ Prolonged "warmup"idling wastes gas.Start
the vehicle justbefore youareready todrive.
Accelerate slowlyandsmoothly.
~ Switch offthe engine ifstationary forlonger
periods.
Maintenance, CarCare ~
Any additional weightcarried inthe vehicle re-
duces fueleconomy. Alwayskeepcargo toa
minimum andremove allunnecessary items.
~ Organize yourtripstotake inseveral errands
in one trip.
~ Allelectrical accessories contributetoin-
creased fuelconsumption.
~ Only switch onthe airconditioning whenneces-
sary.
~ Donot drive withtheRoof Transport System
mounted unlessyouneed it.

The EPA estimated m.p.g.isto be used for
comparison purposes,actualmileage may
be different fromtheestimated m.p.g.,
depending onyour driving speed,weather
conditions andtriplength. Youractual
highway mileagewillprobably beless than
the estimated m.p.g.

~ Please observe alllocal andnational speed
limits.
Operating
YourPorsche inother
Countries

Government regulationsinthe United States and
Canada requirethatautomobiles meetspecific
emission regulations andsafety standards. There-
fore, carsbuiltforthe U.S. andCanada differfrom
vehicles soldinother countries.
If you plan totake your Porsche outsidetheconti-
nentallimits ofthe United States orCanada, there
is the possibility that
- unleaded fuelmay notbeavailable;
- unleaded fuelmay have aconsiderably lower
octane rating.Excessive engineknockandse-
rious damage toboth engine andcatalytic con-
verters couldresult;
- service maybeinadequate duetolack ofprop-
er service facilities, toolsordiagnostic equip-
ment;
- replacement partsmaynotbeavailable orvery
difficult toget.

Porsche cannotberesponsible forthe
mechanical damagethatcould result
because ofinadequate fuel,service orparts
availability.

If you purchased yourPorsche abroadandwant to
bring itback home, besure tofind outabout ship-
ping andforwarding requirements, aswell ascur-
rent import andcustoms regulations.

Fuel

j!\
Warning!
Fuel ishighly flammable andharmful to
health.

l>
Fire, open flame andsmoking areprohibited
when handling fuel.

l>
Avoid contact withskinorclothing.

l>
Donot inhale fuelvapors.

To prevent damage tothe emission control
system andengine:

l>
Never drivethetank completely outoffuel.

l>
Avoid highcornering speedsafterthewarning
lights havecome on.

l>
Please observe thechapter "EMISSION CON-
TROL SYSTEM" onPage 124.
Please observe thechapter "FUELECONOMY"
on Page 120.
Please observe thechapter "LEVELGAUGE"
on Page 63.

Check engine warning light

If the warning lightsinthe instrument panelandon-
board computer comeonand remain onwhile
driving, itsuggests:
- animproperly fastenedtankcap
or

- refuelling withengine running.
Opening
thefiller flap

The filler opening isunder thefiller flapinthe front
right fender.

l>
With thevehicle unlocked, pressonthe front
part ofthe filler flap
(arrow)
toopen theflap.
The filler flapiscentrally lockedalongwiththeoth-
er locks.
If
there isadefect inthe automatic unlocking
system:

l>
Open thepassenger door.

l>
Pull thering inthe right-hand dooraperture
(ar-

row).

l>l>l>

Maintenance, CarCare
21

1.
Important:
Stoptheengine andswitch offthe
FuelRecommendations

ignition.

Refuelling
Fuel tank capacity islisted under "Capacities".
Porsche doesnotrecommend theuse offuel ad-
ditives.

I>
Please observe thechapter "CAPACITIES" on
Page 185.
Maintenance, CarCare 2.
Slowly unscrew thetank cap.
Hang thetank caponthe plastic strapofthe
filler flap.
3. Insert fuel-hose nozzlefullyintothefiller neck
with thehandle ofthe fuel-hose nozzlefacing
down.
4. Donot add further fuelonce thecorrectly op-
erated automatic fuel-hosenozzlehas
switched off.
Fuel could sprayorcould runover inwarm
temperatures.
5. Replace thetank capimmediately after
refuelling andturn ituntil youhear itand feel it
engage.

If you lose thetank cap,youmust replace it
only with anoriginal parttoreduce the
possibility ofafire inthe event ofacollision.
Your
Porsche isequipped withcatalytic convert-
ers and must use
UNLEADED FUELONLY.

Your engine isdesigned toprovide optimum per-
formance andfuel economy usingunleaded premi-
um fuel with anoctane ratingof
98 RON
(93 CLC orAKI).
Porsche therefore recom-
mends theuse ofthese fuelsinyour vehicle.
Porsche alsorecognizes thatthese fuelsmaynot
always beavailable. Beassured thatyour vehicle
will operate properly onunleaded premiumfuels
with octane numbers ofatleast
95RON
(90 CLC orAKI),
sincetheengine's "Electronic
Oktane
™
knock control" willadapt theignition tim-
ing, ifnecessary.

The useofUNLEADED FUELONLY is
critically important tothe lifeofthe catalytic
converters. Depositsfromleaded fuelswill
ruin theconverters andmake itineffective as
an emission controldevice.

Cars withcatalytic converters haveasmaller fuel
tank opening, andgas station pumps havesmaller
nozzles. Thiswillprevent accidental pumpingof
leaded fuelintocars withcatalytic converters.

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