2003 CADILLAC SEVILLE check engine

Highway Hypnosis
Is there actually such a condition as ªhighway
hypnosisº? Or is it just plain falling asleep at the wheel?
Call it highway hypnosis, lack of awareness, or
whatever.
There is something about an easy stretch of road with
the same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush of the
wind against the vehicle that can make you sleepy. Don't
let it happen to you! If it does, your vehicle can leave
the road in
less than a second,and you could crash and
be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
·Make sure your vehicle is well ventilated, with a
comfortably cool interior.
·Keep your eyes moving. Scan the road ahead and
to the sides. Check your rearview mirrors and your
instruments frequently.
·If you get sleepy, pull off the road into a rest,
service or parking area and take a nap, get some
exercise, or both. For safety, treat drowsiness
on the highway as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in ¯at or rolling terrain.
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If you drive regularly in steep country, or if you're
planning to visit there, here are some tips that can make
your trips safer and more enjoyable.
·Keep your vehicle in good shape. Check all ¯uid
levels and also the brakes, tires, cooling system
and transaxle. These parts can work hard on
mountain roads.
·Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you go
down a steep or long hill.
{CAUTION:
If you do not shift down, your brakes could get
so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Shift down
to let your engine assist your brakes on a
steep downhill slope.
{CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. Your brakes will have
to do all the work of slowing down. They could
get so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Always
have your engine running and your vehicle in
gear when you go downhill.
·Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help you climb the
hill better.
·Stay in your own lane when driving on two-lane
roads in hills or mountains. Don't swing wide or
cut across the center of the road. Drive at speeds
that let you stay in your own lane.
·As you go over the top of a hill, be alert. There
could be something in your lane, like a stalled car or
an accident.
·You may see hghway signs on mountains that warn
of special problems. Examples are long grades,
passing or no-passing zones, a falling rocks area or
winding roads. Be alert to these and take
appropriate action.
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·Tie a red cloth to your vehicle to alert police that
you've been stopped by the snow.
·Put on extra clothing or wrap a blanket around you.
If you have no blankets or extra clothing, make
body insulators from newspapers, burlap bags, rags,
¯oor mats Ð anything you can wrap around
yourself or tuck under your clothing to keep warm.
You can run the engine to keep warm, but be careful.{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You can not see it
or smell it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking your exhaust pipe. And check around
again from time to time to be sure snow does
not collect there.
Open a window just a little on the side of the
vehicle that is away from the wind. This will
help keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with your headlamps. Let the
heater run for a while.
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When You Are Ready to Leave After
Parking on a Hill:
1. Apply your regular brakes and hold the pedal down
while you:
·start your engine,
·shift into a gear, and
·make sure the parking brake has released.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transaxle ¯uid (don't over®ll),
engine oil, drive belt, cooling system and brake system.
Each of these is covered in this manual, and the
Index will help you ®nd them quickly. If you're trailering,
it's a good idea to review this information before you
start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-28.
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Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Speci®cations....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-6
Filling a Portable Fuel Container.....................5-10
Checking Things Under
the Hood....................................................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-19
Automatic Transaxle Fluid..............................5-21
Engine Coolant.............................................5-25
Coolant Surge Tank Pressure Cap..................5-28
Engine Overheating.......................................5-28
Cooling System............................................5-31Power Steering Fluid.....................................5-38
Windshield Washer Fluid................................5-39
Brakes........................................................5-40
Battery........................................................5-43
Jump Starting...............................................5-45
Headlamp Aiming...........................................5-51
Headlamp Horizontal Aiming...........................5-53
Headlamp Vertical Aiming..............................5-53
Bulb Replacement..........................................5-55
High Intensity Discharge (HID) Lighting............5-55
Halogen Bulbs..............................................5-56
Headlamps..................................................5-56
Front Turn Signal Lamps...............................5-59
Center High-Mounted Stoplamp (CHMSL).........5-60
Taillamps and Turn Signal Lamps...................5-60
Replacement Bulbs.......................................5-61
Windshield Wiper Blade Replacement..............5-62
Tires..............................................................5-63
In¯ation -- Tire Pressure................................5-64
Tire Pressure Monitor System.........................5-65
Tire Inspection and Rotation...........................5-67
When It Is Time for New Tires.......................5-68
Section 5 Service and Appearance Care
5-1

CAUTION: (Continued)
·
Be sure to use the proper nuts, bolts and
other fasteners. ªEnglishº and ªmetricº
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the air¯ow around it. This may cause wind
noise and affect windshield washer performance. Check
with your dealer before adding equipment to the
outside of your vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
Use regular unleaded gasoline with a posted octane of
87 or higher. However, for best performance and for
trailer towing, you may wish to use middle grade
or premium unleaded gasoline. If the octane is less than
87, you may get a heavy knocking noise when you
drive. If this occurs, use a gasoline rated at 87 octane
or higher as soon as possible. Otherwise, you might
damage your engine.
5-4

Gasoline Speci®cations
It is recommended that gasoline meet speci®cations
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers Association for better
vehicle performance and engine protection. Gasoline
meeting these speci®cations could provide improved
driveability and emission control system performance
compared to other gasoline.
In Canada, look for the
ªAuto Makers' Choiceº
label on the pump.
California Fuel
If your vehicle is certi®ed to meet California Emission
Standards (see the underhood emission control label), it
is designed to operate on fuels that meet California
speci®cations. If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
speci®cations, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on (see
Malfunction Indicator Lamp on page 3-47)
and your vehicle may fail a smog-check test. If this
occurs, return to your authorized GM dealer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs may not be covered
by your warranty.
Canada Only
5-5

Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work
properly. You should not have to add anything to your
fuel. Gasolines containing oxygenates, such as
ethers and ethanol, and reformulated gasolines may be
available in your area to contribute to clean air.
General Motors recommends that you use these
gasolines, particularly if they comply with the
speci®cations described earlier.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system maybe affected. The malfunction indicator lamp may turn
on. If this occurs, return to your authorized GM dealer for
service.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to ®nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
Filling Your Tank
{CAUTION:
Fuel vapor is highly ¯ammable. It burns
violently, and that can cause very bad injuries.
Do not smoke if you are near fuel or refueling
your vehicle. Keep sparks, ¯ames and smoking
materials away from fuel.
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