overheating PORSCHE 911 CARRERA 2003 4.G Owners Manual

41CD
BrakewarninglightUSA
@BrakewarninglightCanada
Ifthewarninglightsintheinstrumentpaneland
on-boardcomputergoonwhiledriving,the
brakefluidlevelmaybetoolow,or(ifthebrake
pedaltravelhasincreased)oneofthetwobrake
circuitsmayhavefailed.
Agreaterbrakingpressurewillberequired,
stoppingdistanceswillbelongerandthebrak-
ingbehaviorwillchange,particularlyincurves.
Withcorrectlyadjustedbrakes,andacorrectly
workingbrakesystem,thepedaltraveltothe
pointofbrakeactuationshouldbe
1-3/16
in.to

1-9/16
in.or30to40mm.
Wheneverthebrakepedaltravelexceedsthis
distance,havethebrakesystemchecked.
54Controls,Instruments
Brakepedal
/!\Warning!
Riskofanaccident.
Anyobstructionofthebrakepedalcould
increasethestoppingdistance.
I>Alwayscheckthemovementofthebrake
pedalbeforedrivingandmakesurethatitis
notobstructedbyafloormatoranyother
object.
I>Securethefloormattopreventitfromsliding
intopositionsthatcouldinterferewiththe
safeoperationofyourvehicle.
YourPorschedealerwillbegladtoofferyou
floormatsofthecorrectsizeincludingase-
curingpossibility.
Note
Incaseoneofthetwobrakecircuitsfails,in-
creasedpedaltravelisrequiredtobringyour
vehicletoafullstop.
/!\Warning!
Toavoidoverheatingandprematurewear
ofthebrakes:
I>Beforedescendingasteepgrade,reduce
speedandshiftthetransmissionintoalower
gearordrivingpositiontocontrolspeed.
I>Donot"ridethebrakes"byrestingyourfoot
onthepedalwhennotintendingtoapply
brakepressure.
I>Donotholdthepedaldowntoolongortoo
often.
Thiscouldcausethebrakestogethotand
notfunctionproperly.

HowEmissionControlWorks
Whenanautomobileengineisrunning,ituses
energygeneratedthroughthecombustionofa
mixtureofairandfuel.Dependingonwhethera
carisdrivenfastorslowlyorwhethertheen-
gineiscoldorhot,someofthefuel(hydrocar-
bons)maynotbeburnedcompletely,butmay
bedischargedintotheenginecrankcaseorex-
haustsystem.Additonalhydrocarbonsmayenter
theatmospherethroughevaporationoffuelfrom
thefueltank.Thesehydrocarbons(HC),whenre-
leasedintotheair,contributetoundesirablepol-
lution.
Inaddition,carbonmonoxide(CO)andoxidesof
nitrogen(NOx)contributetoengineemissions.
They,too,areformedduringthecombustion
processanddischargedintotheexhaustsys-
tem.
Toreducethesepollutants,yourPorscheis
equippedwithapreciselycalibratedfuelinjection
systemtoassureafinelybalancedair/fuelmix-
tureunderalloperatingconditions.
180Maintenance,CarCare
Oxygensensor
Theoxygensensor,installedintheexhaustpipe
continuouslysensestheoxygencontentofthe
exhaustandsignalstheinformationtoanelec-
troniccontrolunit.Thecontrolunitcorrectsthe
air/fuelratio,sotheenginealwaysreceivesan
accuratelymeteredair/fuelmixture.
Crankcaseventilation
Throughcrankcaseventilation,undesirable
emissionsfromtheenginecrankcasearenot
permittedtoreachtheoutsideatmosphere.
Theseemissionsarerecirculatedfromthe
crankcasetotheairintakesystem.Fromhere
theemissionsmixwiththeintakeairandare
laterburnedintheengine.
Catalyticconverters
Thecatalyticconvertersareefficient"clean-up"
devicesbuiltintotheexhaustsystemoftheve-
hicle.Thecatalyticconvertersburntheundesir-
ablepollutantsintheexhaustgasbeforeitis
releasedintotheatmosphere.
Theexclusiveuseofunleadedfueliscriti-
callyimportantforthelifeofthecatalytic
converters.Therefore,onlyunleadedfuel
mustbeused.
Thecatalyticconverterswillbedamaged
by:
-pushortowstartingthevehicle
-misfiringoftheengine
-turningofftheignitionwhilethevehicleis
movingor
-drivinguntilthefueltankiscompletelyempty
-byotherunusualoperatingconditions.
t>Donotcontinuetooperateyourvehicleunder
theseconditions,sincerawfuelmightreach
thecatalyticconverters.Thiscouldresultin
overheatingoftheconverters.Federallaw
prohibitsuseofleadedfuelinthiscar.