tow CADILLAC STS 2006 1.G Service Manual

Engine Compartment Overview
Your vehicle may be equipped with front compartment underhood sight shields, which surround the vehicle’s engine
cover. These sight shields will need to be removed in order to access some of the underhood components in your
vehicle.To remove the sight shields, turn the fasteners on each shield to the left until they pop out. Then remove the
fasteners and lift the shields up and away from the tower to tower brace.
3.6L V6 Engine
5-12

After you have removed the sight shields (if equipped) on the 4.4L V8 STS-V engine, here is what you will see:
A. Battery. SeeBattery on page 5-44.
B. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-106.
C. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-55.
D. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
E. Intercooler System Pressure Cap. SeeEngine
Coolant on page 5-26.
F. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.
G. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-18.
H. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-18.I. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
J. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-30
andCooling System on page 5-32.
K. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-24.
If your vehicle is equipped with front compartment
underhood sight shields, before closing the hood be
sure to reinstall the sight shields. To reinstall the shields,
locate the tabs on the left and right sides and insert
them into the openings in the tower to tower brace.
Then insert the fasteners into the top of the shield and
push the fasteners back into place.
5-17

Engine Oil
Checking Engine Oil
It is a good idea to check your engine oil every time
you get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-12for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
When to Add Engine Oil
V6 Engine
V8 Engine
5-18

4. The two sides of the airbox are hinged at the
bottom. Open the airbox by pushing the top of
the airbox cover toward the engine.
5. Remove the air lter by lifting it straight up through
the opening in the airbox.
6. Inspect or replace the engine air cleaner/lter.
SeeNormal Maintenance Replacement Parts
on page 6-14for the correct part number for
the lter.
7. Reinstall the cover by reversing Steps 1 through 4.
If your vehicle has the 4.4L V8 STS-V engine, there
is a special procedure for checking and changing the air
cleaner/lter. Because this procedure is difficult, you
should have this done at the dealership service
department. Contact your dealer for additional
information or the procedure can be found in the service
manual. To purchase a service manual, seeService
Publications Ordering Information on page 7-14.
{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned.
The air cleaner not only cleans the air; it helps
to stop ames if the engine backres. If it is
not there and the engine backres, you could
be burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre can
cause a damaging engine re. And, dirt can easily get
into your engine, which will damage it. Always have
the air cleaner/lter in place when you are driving.
5-25

Checking Coolant
The coolant surge tank and pressure cap are located on
the driver’s side of the vehicle, toward the rear of the
engine compartment. SeeEngine Compartment
Overview on page 5-12for more information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD/FROID line on the side of the surge tank.
Follow the arrow from the top of the tank down the side
to the horizontal mark.
If the CHECK COOLANT LEVEL message in the Driver
Information Center (DIC) comes on and stays on, it
means you are low on engine coolant. SeeDIC
Warnings and Messages on page 3-79for more
information.
5-28

If No Steam Is Coming From
Your Engine
An overheat warning, along with a CHECK COOLANT
LEVEL message, can indicate a serious problem.
If you get an engine overheat warning with no CHECK
COOLANT LEVEL message, but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the road,
shift to PARK (P) or NEUTRAL (N) and let the
engine idle.
2. Set the climate controls to the highest heat setting
and fan speed and open the windows, as
necessary.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.If the warning continues and you have not stopped,
pull over, stop, and park your vehicle right away.
If there is still no sign of steam, you can idle the engine
for three minutes while you are parked. If you still have
the warning, turn off the engine and get everyone out of
the vehicle until it cools down. Also, see “Overheated
Engine Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get service
help right away.
Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Should an overheated
engine condition exist, an overheat protection mode
which alternates ring groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss
in power and engine performance. A low coolant and/or
engine overheat warning will indicate that an overheat
condition exists. Driving extended miles (km) and/or
towing a trailer in the overheat protection mode should
be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss and change the oil. SeeEngine
Oil on page 5-18.
5-31

Vehicles that have the Tire Pressure Monitor System
(TPMS) will need to have the TPMS sensors reset after
a tire rotation, seeTire Pressure Monitor System on
page 5-66.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque” underCapacities and
Specications on page 5-116.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if needed, to get all
the rust or dirt off. SeeChanging a Flat Tire
(STS Only) on page 5-83.
When It Is Time for New Tires
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining.
You need a new tire if any of the following statements
are true:
You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut, or snagged
deep enough to show cord or fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage that
cannot be repaired well because of the size or
location of the damage.
5-71

Lifting Your Vehicle (STS-V )
{CAUTION:
Lifting a vehicle can cause an injury. The
vehicle can slip off the jack and roll over you
or other people. You and they could be badly
injured. Find a level place to lift your vehicle.
To help prevent the vehicle from moving:
1. Hold the brake pedal down with your
right foot.
2. Move the shift lever in PARK (P) by
pressing the button on the front of the
shift lever while pushing the lever all the
way toward the front of the vehicle.
Release the button.
3. With your right foot still holding the brake
pedal down, set the parking brake with
your left foot.
4. Turn off the engine.
To be even more certain the vehicle will not
move, you can put blocks in front of and
behind the wheels. Also, seeShifting Into
Park (P) on page 2-36andParking Brake on
page 2-35for additional information.
{CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack, you
could be badly injured or killed. Never get under
a vehicle when it is supported only by a jack.
{CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal
injury and vehicle damage, be sure to place
the jack in the proper location before raising
the vehicle.
If you ever use a jack to lift your vehicle, follow the
instructions that came with the jack, and be sure to
use the correct lifting points to avoid damaging
your vehicle.
5-79

Lifting From the Rear
The rear lifting points can be accessed from either side
of your vehicle, in front of the rear tires.
1. Locate the rear lifting points using the diagram
above. The rear lifting location is about 7 inches
(17 cm) from the front edge of the rear wheel well.
2. Be sure to place a block or pad between the jack
and the vehicle.
3. Lift the vehicle with the jack, making sure the jack
is centered on the rear lifting point.
SeeDoing Your Own Service Work on page 5-4.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your tires properly. See
Tires on page 5-56. If air goes out of a tire, It is much
more likely to leak out slowly. But if you should ever
have a blowout, here are a few tips about what to expect
and what to do:
If a front tire fails, the at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout, remove your foot from
the accelerator pedal. Get the vehicle under control
by steering the way you want the vehicle to go. It may
be very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road if possible.
5-81

8. Raise the vehicle by turning the wheel wrench
clockwise. Raise the vehicle far enough off the
ground for the compact spare tire to t under the
vehicle.9. Remove all the wheel
nuts and take off the
at tire.
{CAUTION:
Rust or dirt on the wheel, or on the parts to
which it is fastened, can make the wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
the places where the wheel attaches to the
vehicle. In an emergency, you can use a cloth
or a paper towel to do this; but be sure to use
a scraper or wire brush later, if needed, to get
all the rust or dirt off.
5-89