2004 PORSCHE CAYENNE catalytic converter

Multi-Purpose Display and Instruments
123
Emission ControlThe emission control system detects malfunctions
early that could, for example, cause increased
pollutant emissions or consequential damage.
Faults are indicated by a continuously lit or
flashing instrument panel warning light.
The faults are recorded in the control unit's fault
memory.
The warning light in the instrument panel lights up
when the ignition is switched on as a bulb check
and goes out approx. 4 seconds after the engine
starts. If the warning light does not light up, have
the bulb replaced promptly.The warning light in the instrument panel flashes to
indicate operating states (e.g. engine misfiring)
which might cause damage to certain parts of the
emission control system.
fIn this case, immediately reduce the engine
load by easing off the accelerator.
fIn order to avoid consequential damage to the
engine or emission control system (e.g. cata-
lytic converter), have the fault diagnosed and
rectified immediately at the nearest authorized
Porsche dealer.
If the warning light in the instrument panel lights up
permanently without flashing before and remains
on while driving, it suggests:
– a potential engine control problem and the
need for system service or
– an improperly fastened tank cap or
– the vehicle was refueled while the engine was
running.
fStop immediately at a suitable and secure
place and check tank cap for proper fastening.
If tank cap was fastened correctly, see your
authorized Porsche dealer for service as soon
as possible.
Caution!
If the check engine warning light in the in-
strument panel is flashing, serious catalytic
converter damage and power loss will soon
occur.
Prolonged driving with the check engine
warning light on could cause damage to the
emission control system. It also could affect
fuel economy and driveability.
fHave the fault remedied at the nearest authorized Porsche dealer immediately.
Check engine warning light
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264
Maintenance and Car Care
Parking
Danger!
Danger of fire resulting in serious personal
injury or death.
fDo not park or operate the vehicle in areas
where the hot exhaust system may come in
contact with dry grass, brush, fuel spill or
other flammable material.
fIf your car catches on fire for any reason, call
the fire department. Do not endanger your life by attempting to put out the fire.
Undercoating
Danger!
Danger of fire resulting in serious personal
injury or death.
fDo not apply additional undercoating or rust-
proofing on or near the exhaust manifold,
exhaust pipes, catalytic converters or heat
shields. During driving the substance used for undercoating could overheat and ignite.
How Emission Control WorksWhen an automobile engine is running, it uses
energy generated through the combustion of a
mixture of air and fuel. Depending on whether a
car is driven fast or slowly or whether the engine
is cold or hot, some of the fuel (hydrocarbons)
may not be burned completely, but may be
discharged into the engine crankcase or exhaust
system. Additonal hydrocarbons may enter the
atmosphere through evaporation of fuel from the
fuel tank. These hydrocarbons (HC), when
released into the air, contribute to undesirable
pollution.
In addition, carbon monoxide (CO) and oxides of
nitrogen (NOx) contribute to engine emissions.
They, too, are formed during the combustion
process and discharged into the exhaust system.
To reduce these pollutants, your Porsche is
equipped with a precisely calibrated fuel injection
system to assure a finely balanced air/fuel mixture
under all operating conditions.
Oxygen sensorThe oxygen sensor, installed in the exhaust pipe
continuously senses the oxygen content of the ex-
haust and signals the information to an electronic
control unit. The control unit corrects the air/fuel
ratio, so the engine always receives an accurately
metered air/fuel mixture.Crankcase ventilationThrough crankcase ventilation, undesirable
emissions from the engine crankcase are not per-
mitted to reach the outside atmosphere. These
emissions are recirculated from the crankcase to
the air intake system. From here the emissions
mix with the intake air and are later burned in the
engine.Catalytic convertersThe catalytic converters are efficient “clean-up”
devices built into the exhaust system of the
vehicle. The catalytic converters burn the
undesirable pollutants in the exhaust gas before it
is released into the atmosphere.
The exclusive use of unleaded fuel is critical-
ly important for the life of the catalytic con-
verters. Therefore, only unleaded fuel must
be used.
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Maintenance and Car Care
265
The catalytic converters will be damaged by:
– push or tow starting the vehicle
– misfiring of the engine
– turning off the ignition while the vehicle is
moving or
– driving until the fuel tank is completely empty
– by other unusual operating conditions.
fDo not continue to operate your vehicle under
these conditions, since raw fuel might reach
the catalytic converters. This could result in
overheating of the converters. Federal law
prohibits use of leaded fuel in this car.
Fuel EconomyFuel 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 to the 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.
fAny additional weight carried in the vehicle
re d u c e s f u e l e c o n o m y. A l w a ys k e e p c a rg o t o a
minimum and remove all unnecessary items.
fOrganize your trips to take in several errands
in one trip.
fAll electrical accessories contribute to
increased fuel consumption.
fOnly switch on the air conditioning when neces-
sary.
fDo not drive with the Roof Transport System
mounted unless you need it.
The EPA estimated miles per gallon (mpg) is
to be used for comparison purposes, actual
mileage may be different from the estimated
mpg, depending on your driving speed,
weather conditions and trip length. Your
actual highway mileage will probably be less
than the estimated mpg.
fPlease see all local and national speed limits.
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266
Maintenance and Car Care
Operating Your Porsche in other
CountriesGovernment 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
serious damage to both engine and catalytic
converters could result;
– service may be inadequate due to lack of
proper service facilities, tools or diagnostic
equipment;
– 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
current import and customs regulations.
Fuel
Warning!
Fuel is highly flammable and harmful to
health.
fFire, open flame and smoking are prohibited
when handling fuel.
fAvoid contact with skin or clothing.
fDo not inhale fuel vapours.
To prevent damage to the emission control
system and engine:
fNever drive the tank completely out of fuel.
fAvoid high cornering speeds after the warning lights have come on.
To avoid permanent damage to the functionality of
the catalytic converters and oxygen sensors, use
only unleaded fuel.
The engine is designed to provide optimum
performance and fuel consumption if unleaded
premium fuel with 98 RON/88 MON is used.
If unleaded premium fuels with octane numbers of
at least 95 RON/85 MON are used, the
engine's knock control automatically adapts the
ignition timing.The emission control system can be damaged in
various ways (e.g. fueling incorrectly, shortage of
fuel, tow-starting).
fPlease see the chapter “HOW EMISSION
CONTROL WORKS” on Page 264.
fPlease see the chapter “DISPLAYING STATUS
OF LEVEL CONTROL” on Page 131.
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Maintenance and Car Care
269
Fuel RecommendationsYour Porsche is equipped with catalytic conver-
ters and must use UNLEADED FUEL ONLY.
Your engine is designed to provide optimum
performance and fuel economy using unleaded
premium fuel with an octane rating of 98 RON
(93 CLC or AKI). Porsche therefore recom-
mends the use of these fuels in your vehicle.
Porsche also recognizes that these fuels may not
always be available. Be assured that your vehicle
will operate properly on unleaded premium fuels
with octane numbers of at least 95 RON
(90 CLC or AKI), since the engine's “Electronic
Octane™ knock control” will adapt the ignition
timing, if necessary.
It is important to observe the regular service inter-
vals, and particularly the oil change intervals, spe-
cified in your Maintenance Schedule.
The use of UNLEADED FUEL ONLY is critically
important to the life of the catalytic
converters. Deposits from leaded fuels will
ruin the converters and make it ineffective
as an emission control device.
Cars with catalytic converters have a smaller fuel
tank opening, and gas station pumps have smaller
nozzles. This will prevent accidental pumping of
leaded fuel into cars with catalytic converters.Unleaded fuels may not be available outside the
continental U.S. and Canada. Therefore, we
recommend you do not take your car to areas or
countries where unleaded fuel may not be
available.
Octane ratingsOctane rating indicates a fuel's ability to resist
detonation. Therefore, buying the correct octane
gas is important to prevent engine “damage”.
The RON octane rating is based on the research
method. The CLC (U.S. Cost of Living Council oc-
tane rating) or AKI (antiknock index) octane rating
usually displayed on U.S. fuel pumps is calculated
as research octane number plus motor octane
number, divided by 2, that is written as:
The CLC or AKI octane rating is usually lower than
the RON rating:
For example: 95 RON corresponds 90 CLC or
“AKI”
fDo not use fuel additives without Porsche
approval.
Fuels containing ethanolfDo not use any fuels containing more than 10
percent ethanol by volume.
We recommend, however, to change to a different
fuel or station if any of the following problems
occur with your vehicle:
– Deterioration of driveability and performance.
– Substantially reduced fuel economy.
– Vapor lock and non-start problems, especially
at high altitude or at high temperature.
– Engine malfunction or stalling.
RON MON+
2 ----------------------------------
orRM+
2 ---------------
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Maintenance and Car Care
275
UndercoatingThe underside of your car is durably protected
against chemical and mechanical influences.
As it is not possible to exclude the risk of damage
to this protective coating in day to day driving, it
is advisable to have the underside of the car
inspected at certain intervals - preferably before
the start of winter and again in spring - and the
undercoating restored as necessary.
Your authorized Porsche dealer is familiar with the
bodyseal treatment procedures and has the ne-
cessary equipment for applying factory approved
materials. We recommend that you entrust them
with such work and inspections.
Unlike conventional spray oils, undercoating and
rust-proofing compounds based on bitumen or
wax do not attack the sound-proofing materials
applied at the factory.
Warning!
Danger of fire resulting in serious personal
injury or death.
fDo not apply additional undercoating or rust-
proofing on or near the exhaust manifold,
exhaust pipes, catalytic converters or heat
shields. During driving the substance used for undercoating could overheat and ignite.fBefore applying fresh underseal, carefully re-
move deposits or dirt and grease. Once it has
dried, the new undercoating compound forms
a tough protective coating which provides effi-
cient rust-proofing of the floor panels and com-
ponents.
fAlways apply a fresh coating of suitable pre-
servative to unprotect areas after cleaning the
underside of the body, the transmission, the
engine or carrying out repairs to underbody,
engine or transmission components.
Effective rust-proofing is particularly important
during the cold weather season. If your car is
driven frequently in areas where salt has been
spread on the roads, the whole engine compart-
ment should be cleaned thoroughly after the
winter to prevent salt from causing any lasting
damage. A full under-body wash should also be
performed at the same time.
Cleaning headlights, lights, interior and
exterior plastic parts, adhesive filmsObserve the following points:
fUse only clean water and a little dishwashing
detergent or interior window cleaner to clean
headlights, lights, plastic parts, adhesive films
and surfaces.
Use a soft sponge or a soft, lint-free cloth.
Note
An interior window cleaner can also be used to
clean plastic surfaces (observe cleaning instruc-
tions on the container!).
We recommend the Porsche interior window
cleaner.
fGently wipe the surface without applying too
much pressure.
fDo not clean when dry.
fNever use other chemical cleaners or
solvents.
Rinse cleaned surfaces with clear water.
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Minor Repairs
319
Fuse assignment – fuse box in engine compartmentNotes
fUse the plastic grippers from the fuse boxes in the dashboard to replace the fuses.
Fuse numbers that are not listed in the table are not assigned in the fuse box.
fFor information on the fuse plan: Please see the chapter “FUSE PLAN AND FUSE BOX IN ENGINE COMPARTMENT” on Page 313. Cayenne
No.Cayenne S/Cayenne GTS/
Cayenne S Transsyberia
No.Designation Rating in A
1
1
Fan
60
22Fan30
7
7
Ignition coils
15
8 - Ignition coils15
-8Tank vent valve, air-conditioning compressor, air-conditioning control unit, intake pipe switch-
over, crankcase vent15
9
-
Engine control unit
20
-
9
Quantity control valve, camshaft adjuster, valve lift adjuster
15
10 -Water run-on pump relay, tank leakage detection, carbon canister shut-off valve, fan, pressure
sensor for air conditioner10
-10Cooling air output stages, pressure sensor for air conditioner,tank leakage detection, exhaust
flap control valve, oil-level sensor10
11
-
Oil-level sensor, air-conditioning compressor, air-conditioning control unit, crankcase vent
15
-
11
Engine control unit, fuel valve
15
12 - Camshaft adjustment, tank vent, fuel valve, variable intake manifold 10
13
13
Fuel pump, right
15
14 14 Fuel pump, left15
15
15
Engine control unit, main relay
10
17 17 Oxygen sensors ahead of catalytic converter 15
18
18
Oxygen sensors behind catalytic converter
7.5
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Minor Repairs
323
Emergency Starting with Jumper
CablesIf the battery is discharged, e.g. in winter or after
the car has been parked for a long time, the bat-
tery of another car can be used for starting with
the help of jumper cables.
Make sure the voltage of both batteries is the
same.
The capacity (Ampere hours, Ah) of the booster
battery must not be substantially less than that of
the discharged battery.The discharged battery
must be correctly connected to the vehicle's elec-
trical system.
fPlease see the chapter “BATTERY” on
Page 320.
Note
Do not try to start the car by pushing or towing.
Damage to the catalytic converters and other
components of the car may result.
Danger!
Risk of short circuit, damage and explosion,
resulting in serious personal injury or death.
fUse only jumper cables of adequate diameter
cross-section and fitted with completely
insulated alligator clips.
fFollow all warnings and instructions of the
jumper cable manufacturer.
fWhen connecting jumper cables, make sure
that they cannot get caught in any moving
parts in the engine compartment.
The jumper cables must be long enough so
that neither vehicles nor cables touch another.
fThe vehicles must not be in contact, otherwise
current might flow as soon as the positive
terminals are connected.
fThe cable clamps must not be allowed to con-
tact each other when one end of the jumper ca-
bles are connected to a battery.
fCarefully ensure that tools or conductive jewe-
lery (rings, chains, watch straps) do not come
into contact with the positive jumper cable or
the positive battery post.
fImproper hook-up of jumper cables can ruin
the alternator.
Danger of caustic burns.
fDo not lean over the battery.Danger of gas explosion.
fImproper use of booster battery to start a
vehicle may cause an explosion, resulting in
serious personal injury or death.
fKeep sources of ignition away from the
battery, e.g. open flame, burning cigarettes or
sparking due to cable contact or welding work.
fA discharged battery can freeze even at
14 °F (−10 °C). Before connecting jumper
cables, a frozen battery must be thawed out.
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