check engine CADILLAC STS 2009 1.G Owner's Guide

How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/lter remove the lter from the
vehicle and lightly shake the lter to release loose dust
and dirt. If the lter remains caked with dirt, a new lter
is required.
To inspect or replace the lter in the 3.6L V6 or
4.6L V8 engines, do the following:
1. Remove the two screws located on the top of
the cover.
2. Disconnect the coolant recovery hose so that
it is not going across the top of the engine air
cleaner/lter.
3. Loosen the clamp and remove the duct from the
passenger’s side of the engine air cleaner/lter.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.
SeeMaintenance Replacement Parts on page 6-15
for 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 7-15.
5-24

{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 the engine, which will damage it. Always have
the air cleaner/lter in place when you are driving.
Automatic Transmission Fluid
How to Check Automatic Transmission
Fluid
It is not necessary to check the transmission uid level.
A transmission uid leak is the only reason for uid loss.
If a leak occurs, take the vehicle to the dealer/retailer
service department and have it repaired as soon as
possible.
There is a special procedure for checking and changing
the transmission uid. Because this procedure is
difficult, you should have this done at the dealer/retailer
service department. Contact your dealer/retailer for
additional information or the procedure can be found
in the service manual. To purchase a service manual,
seeService Publications Ordering Information on
page 7-15.
Notice:Use of the incorrect automatic transmission
uid may damage the vehicle, and the damages
may not be covered by the vehicle’s warranty.
Always use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-13.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the uid listed inRecommended Fluids and
Lubricants on page 6-13.
5-25

CAUTION: (Continued)
Do not run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine re, and you could be burned.
Get any leak xed before you drive the vehicle.
Notice:Using coolant other than DEX-COOL
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant
in the vehicle.
Engine Coolant
The cooling system in the vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst.
The following explains the cooling system and how to
check and add coolant when it is low. If there is a problem
with engine overheating, seeEngine Overheating on
page 5-34.
5-27

Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
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.Check to see if coolant is visible in the coolant surge
tank. If the coolant inside the coolant surge tank is boiling,
do not do anything else until it cools down. If coolant
is visible but the coolant level is not at or above the
FULL COLD/FROID line, add a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant at the coolant
surge tank, but be sure the cooling system is cool before
this is done.
When the engine is cold, the coolant level should be at
or above the FULL COLD/FROID line on the side of the
coolant surge tank. Follow the arrow from the top of the
tank down the side to the horizontal mark. If it is not,
there could be a leak in the cooling system.
If the coolant is low, add the coolant or take the vehicle
to a dealer/retailer for service.
5-29

Checking Intercooler System Coolant
(4.4L V8 STS-V Engine Only)
The vehicle must be on a level surface when checking
the coolant level.
SeeEngine Compartment Overview on page 5-12for
the location of the intercooler system pressure cap.
Turn off the engine. When the engine is cold, the coolant
level should be visible in the intercooler ll neck.
How to Add Coolant to the Surge Tank
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot enough.
Do not spill coolant on a hot engine.
Notice:This vehicle has a specic coolant ll
procedure. Failure to follow this procedure could
cause the engine to overheat and be severely
damaged.
5-30

How to Add Coolant to the
Intercooler System Fill Neck
(4.4L V8 STS-V Engine Only)
Turn the engine off and allow it to cool down, then
check to see if coolant is visible within the horizontal tube
section of the ll neck. If coolant is not visible, add a
50/50 mixture of clean, drinkable water and DEX-COOL
®
coolant to the ll neck. Be sure the Intercooler System,
including the Intercooler System pressure cap, is cool
before doing so. SeeEngine Coolant on page 5-27for
more information.
{CAUTION:
Turning the Intercooler System pressure cap when
the engine and intercooler are hot can allow steam
and scalding liquids to blow out and burn you badly.
Never turn the Intercooler System pressure cap,
even a little, when the engine and intercooler
are hot.1. Remove the Intercooler System pressure cap
when the Intercooler System, including the upper
intercooler hoses, are no longer hot. Turn the
pressure cap slowly counterclockwise about
one-quarter of a turn. If you hear a hiss, wait for
that to stop. This allows any pressure still left to
be vented.
2. Then keep turning the pressure cap slowly, and
remove it.
5-33

You may decide not to lift the hood when this warning
appears, but instead get service help right away.
SeeRoadside Service on page 7-7.
If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run
the engine and have the vehicle serviced.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-36for information on driving to a safe place
in an emergency.
Notice:If the engine catches re while driving
with no coolant, the vehicle can be badly damaged.
The costly repairs would not be covered by the
vehicle warranty. SeeOverheated Engine Protection
Operating Mode on page 5-36for information on
driving to a safe place in an emergency.If Steam Is Coming From The Engine
Compartment
{CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no sign
of steam or coolant before you open the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch re. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating Mode
on page 5-36for information on driving to a safe
place in an emergency.
5-35

Power Steering Fluid
SeeEngine Compartment
Overview on page 5-12for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How to Check Power Steering Fluid
To check the power steering uid, do the following:
1. Turn the ignition off and let the engine compartment
cool down.
2. Wipe the cap and the top of the reservoir clean.
3. Unscrew the cap and wipe the dipstick with a
clean rag.
4. Replace the cap and completely tighten it.
5. Remove the cap again and look at the uid level on
the dipstick.
The level should be within the HOT mark. If necessary,
add only enough uid to bring the level within the mark.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-13.
Always use the proper uid.
Notice:Use of the incorrect uid may damage
the vehicle and the damages may not be covered by
the vehicle’s warranty. Always use the correct uid
listed inRecommended Fluids and Lubricants on
page 6-13.
5-37

Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure to read
the manufacturer’s instructions before use. If you will be
operating your vehicle in an area where the temperature
may fall below freezing, use a uid that has sufficient
protection against freezing.
Adding Washer Fluid
The CHECK WASHER FLUID message will appear
on the Driver Information Center (DIC) when the uid
level is low. SeeDIC Warnings and Messages on
page 3-79for more information.
Open the cap with the
washer symbol on it.
Add washer uid until the
tank is full. SeeEngine
Compartment Overview
on page 5-12for reservoir
location.Notice:
When using concentrated washer uid, follow
the manufacturer’s instructions for adding water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts of
the washer system. Also, water does not clean as
well as washer uid.
Fill the washer uid tank only three-quarters
full when it is very cold. This allows for uid
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage the vehicle’s
windshield washer system and paint.
5-38

Brakes
Brake Fluid
The brake master
cylinder reservoir is lled
with DOT-3 brake uid.
SeeEngine Compartment
Overview on page 5-12
for reservoir location and
access.
There are only two reasons why the brake uid level in
the reservoir might go down:
The brake uid level goes down because of normal
brake lining wear. When new linings are installed,
the uid level goes back up.
A uid leak in the brake hydraulic system can also
cause a low uid level. Have the brake hydraulic
system xed, since a leak means that sooner
or later the brakes will not work well.Do not top off the brake uid. Adding uid does not
correct a leak. If uid is added when the linings are worn,
there will be too much uid when new brake linings are
installed. Add or remove brake uid, as necessary, only
when work is done on the brake hydraulic system.
{CAUTION:
If too much brake uid is added, it can spill on the
engine and burn, if the engine is hot enough. You
or others could be burned, and the vehicle could
be damaged. Add brake uid only when work is
done on the brake hydraulic system.
If the ignition is on and the brake uid is low, the
CHECK BRAKE FLUID message displays in the
Driver Information Center (DIC). SeeDIC Warnings
and Messages on page 3-79.
5-39