2007 CADILLAC CTS V check engine

If your vehicle has the 6.0L V8 engine (VIN
Code U), use premium unleaded gasoline with a
posted octane rating of 91 or higher. You may also
use regular unleaded gasoline rated at 87 octane or
higher, but your vehicle’s acceleration may be
slightly reduced, and you may notice a slight
audible knocking noise, commonly referred to as
spark knock. If the octane is less than 87, you may
notice 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. If you are using gasoline
rated at 87 octane or higher and you hear heavy
knocking, your engine needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 336for additional information.
California Fuel
If your vehicle is certied to meet California
Emissions Standards, it is designed to operate on
fuels that meet California specications. See
the underhood emission control label. If this fuel is
not available in states adopting California
emissions standards, your vehicle will operate
satisfactorily on fuels meeting federal
specications, but emission control system
performance may be affected. The malfunction
indicator lamp may turn on and your vehicle may
fail a smog-check test. SeeMalfunction Indicator
Lamp on page 209. 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.
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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 the Tank
{CAUTION:
Fuel vapor burns violently and a fuel re
can cause bad injuries. To help avoid
injuries to you and others, read and follow
all the instructions on the pump island.
Turn off your engine when you are
refueling. Do not smoke if you are near
fuel or refueling your vehicle. Do not use
cellular phones. Keep sparks, ames, and
smoking materials away from fuel. Do not
leave the fuel pump unattended when
refueling your vehicle. This is against the
law in some places. Do not re-enter the
vehicle while pumping fuel. Keep children
away from the fuel pump; never let
children pump fuel.The tethered fuel cap is located behind a hinged
fuel door on the passenger’s side of the vehicle.
To open the fuel door, push inward on the forward
edge of the fuel door until the rear edge can be
pulled outward.
To remove the fuel cap, turn it slowly
counterclockwise. The fuel cap has a spring in it; if
the cap is released too soon, it will spring back
to the right.
While refueling, hang the tethered fuel cap from
the hook on the fuel door.
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Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing, and tools
away from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine
parts and start a re. These include
liquids like fuel, oil, coolant, brake uid,
windshield washer and other uids, and
plastic or rubber. You or others could be
burned. Be careful not to drop or spill
things that will burn onto a hot engine.
340

A. Underhood Fuse Block. SeeUnderhood Fuse
Block on page 447.
B. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 369.
C. Battery. SeeBattery on page 375.
D. Passenger Compartment Air Filter. See
Passenger Compartment Air Filter on page 195.
E. Power Steering Fluid Reservoir (Under
Engine Cover). SeePower Steering Fluid on
page 368.
F. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil on page 346.G. Engine Oil Dipstick (Out of View). See
“Checking Engine Oil” underEngine Oil on
page 346.
H. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 371.
I. Hydraulic Clutch Reservoir (If Equipped) (Not
Shown). See “When to Check and What to Use”
underHydraulic Clutch on page 356.
J. Engine Coolant Surge Tank and Pressure Cap.
SeeCoolant Surge Tank Pressure Cap on
page 360andCooling System on page 363.
K. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 351.
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A. Underhood Fuse Block. SeeUnderhood Fuse
Block on page 447.
B. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 369.
C. Battery. SeeBattery on page 375.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 346.
E. Passenger Compartment Air Filter. See
Passenger Compartment Air Filter on page 195.
F. Engine Oil Fill Cap. See “When to Add
Engine Oil” underEngine Oil on page 346.G. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 368.
H. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 371.
I. Hydraulic Clutch Reservoir. See “When to
Check and What to Use” underHydraulic
Clutch on page 356.
J. Engine Coolant Surge Tank and Pressure Cap.
SeeCoolant Surge Tank Pressure Cap on
page 360andCooling System on page 363.
K. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 351.
345

Engine Oil
There is an oil pressure
light in the instrument
cluster and an Oil
Pressure Low - Stop
Engine message on the
Driver Information
Center (DIC).
If the light and/or message appear, check the
engine oil level right away. For more information,
see “Oil Pressure Low - Stop Engine” under
DIC Warnings and Messages on page 232andOil
Pressure Light on page 212. You should check
the engine oil level regularly; this is an added
reminder.
Checking Engine Oil
It is a good idea to check the 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.
SeeEngine Compartment Overview on page 342
for 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.
346

Your vehicle’s engine is lled at the factory
with a Mobil 1®synthetic oil, which meets all
requirements for your vehicle.
Substitute Engine Oil: When adding oil to maintain
engine oil level, oil meeting GM Standard
GM4718M may not be available. You can add
substitute oil designated SAE 5W-30 with
the starburst symbol at all temperatures. Substitute
oil not meeting GM Standard GM4718M should
not be used for an oil change.
Engine Oil Additives
Do not add anything to the oil. The recommended
oils with the starburst symbol that meet GM
standards are all you need for good performance
and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you
know when to change the engine oil and lter.
This is based on engine revolutions and engine
temperature, and not on mileage. Based on driving
conditions, the mileage at which an oil changewill be indicated can vary considerably. For the oil
life system to work properly, you must reset the
system every time the oil is changed.
When the system has calculated that oil life has
been diminished, it will indicate that an oil change is
necessary. A change engine oil message in the
Driver Information Center (DIC) will come on.
Change your oil as soon as possible within the next
600 miles (1 000 km). It is possible that, if you are
driving under the best conditions, the oil life system
may not indicate that an oil change is necessary for
over a year. However, your engine oil and lter
must be changed at least once a year and at this
time the system must be reset. Your dealer has
GM-trained service people who will perform this
work using genuine GM parts and reset the system.
It is also important to check your oil regularly and
keep it at the proper level.
If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km)
since your last oil change. Remember to reset the
oil life system whenever the oil is changed.
349

To reset the transmission uid life indicator, use the
following steps:
1. Press the up or down arrow on the INFO
(Information) button located to the right of the
DIC display to access the DIC menu.
2. Once the XXX% TRANS FLUID LIFE menu
item is highlighted, press and hold the CLR
button.
The percentage will return to 100, and the
transmission uid life indicator will be reset.
3. Repeat the steps if the percentage does not
return to 100.
Navigation System
If your vehicle has a navigation system, see your
Navigation System Manual for instructions on
how to acknowledge the Change Trans Fluid
message and reset the transmission uid
life indicator.
Manual Transmission Fluid
When to Check Manual Transmission
Fluid
It is not necessary to check the manual
transmission uid level. A transmission uid leak is
the only reason for uid loss. If a leak occurs, take
the vehicle to your GM dealer service department
and have it repaired as soon as possible.
How to Check Manual Transmission
Fluid
Because this operation can be difficult, you may
choose to have this done at your GM dealer
service department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that
some of the uid could come out and fall on hot
engine parts or exhaust system parts, starting a
re. Too little uid could cause the
transmission to overheat. Be sure to get an
accurate reading if you check your
transmission uid.
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