engine CADILLAC CT4 2023 Owners Manual

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 383
possible. See Recommended
Fluids and Lubricants0474
for the proper fluid to use.
Hydraulic Clutch
For vehicles with a manual
transmission, it is not
necessary to regularly check
brake/clutch fluid unless there
is a leak suspected. Adding
fluid will not correct a leak.
A fluid loss in this system
could indicate a problem. Have
the system inspected and
repaired.
When to Check and What
to Use
The brake/hydraulic clutch
fluid reservoir cap has this
symbol on it. See Engine
Compartment Overview 0373
for reservoir location. The common hydraulic clutch
and brake master cylinder fluid
reservoir is filled with brake
fluid as indicated on the
reservoir cap. See Brake Fluid
0
398 for brake fluid to use.
How to Check and Add
Fluid
Visually check the brake/
clutch fluid reservoir to make
sure the fluid level is at the
MIN (minimum) line on the side
of the reservoir. The brake/
hydraulic clutch fluid system
should be closed and sealed.
Do not remove the cap to
check the fluid level or to
top-off the fluid level. Remove
the cap only when necessary
to add the proper fluid until
the level reaches the MIN line.
Engine Air Filter Life
System
This feature provides the
engine air filter’s remaining life
and best timing for a change.
The timing to change an engine air filter depends on
driving and environmental
conditions.
When to Change the
Engine Air Filter
When the Driver Information
Center (DIC) displays a
message to replace the engine
air filter at the next oil change,
follow this timing.
When the DIC displays a
message to replace the engine
air filter soon, replace the
engine air filter at the earliest
convenience.
The system must be reset
after the engine air filter is
changed.
If the DIC displays a message
to check the engine air filter
system, see your dealer.
How to Reset the Engine
Air Filter Life System
To reset:
1. Place the vehicle in P (Park).

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
384 Vehicle Care
2. Display the Air Filter Lifeon the DIC. See Driver
Information Center (DIC)
(Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
3. Press
Ton the steering
wheel, or press the trip
odometer reset stem if the
vehicle does not have DIC
controls, to move to the
Reset/Disable display area.
Select Reset, then press
the thumbwheel or press
the reset stem for several
seconds.
4. Press the thumbwheel or the reset stem to confirm
the reset.
Engine Air
Cleaner/Filter
The engine air cleaner/filter is
in the engine compartment on
the passenger side of the
vehicle for the 2.0L L4 and
2.7L L4 engines, and in the
center of the engine compartment for the 3.6L
V6 engine. See Engine
Compartment Overview
0373.
When to Inspect the
Engine Air Cleaner/Filter
.For intervals on changing
and inspecting the engine air
filter, see Maintenance
Schedule 0469.
.If equipped with Engine Air
Filter Life System, see
Engine Air Filter Life System
0383.
.If driving in very dusty areas,
follow the engine air filter
inspecting and changing
intervals, see Maintenance
Schedule 0469.
How to Inspect/Replace
the Engine Air
Cleaner/Filter
Do not start the engine or
have the engine running with
the engine air cleaner/filter
housing open. Before
removing the engine air
cleaner/filter, make sure that
the engine air cleaner/filter housing and nearby
components are free of dirt
and debris.
Do not clean the engine air
cleaner/filter or components
with water or compressed air.
{Warning
Operating the engine with
the air cleaner/filter off can
cause you or others to be
burned. Use caution when
working on the engine. Do
not start the engine or drive
the vehicle with the air
cleaner/filter off, as flames
may be present if the engine
backfires.
Caution
If the air cleaner/filter is off,
dirt can easily get into the
engine, which could damage
it. Always have the air
cleaner/filter in place when
driving.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 385
To inspect or replace the air
cleaner/filter:
2.0L L4 Engine Shown, 2.7LL4 Engine Similar
1. Remove the five screws on top of the air cleaner/filter
cover.
2. Lift the air/cleaner/filter cover away from the air
cleaner/filter housing.
3. Pull out the air cleaner/filter.
{Warning
If part replacement is
necessary, the part must be
replaced with one of the
same part number or with an
equivalent part. Use of a
replacement part without
the same fit, form, and
function may result in
personal injury or damage to
the vehicle.
4. Inspect or replace the air cleaner/filter.
5. Reverse Steps 1–3 to reinstall the air
cleaner/filter cover.
6. If equipped, reset the engine air filter life system
after replacing the engine
air filter. See Engine Air
Filter Life System 0383.
3.6L V6 Engine
1. Air Duct Clamps
2. Electrical Connectors
3. Screws
1. Disconnect the harness
connectors from the air
cleaner/filter cover
electrical connectors (2).
2. Loosen the screws on the air duct clamps (1) holding
the air outlet ducts in
place. Do not remove
clamps. Move the ducts
aside.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
386 Vehicle Care
3. Remove the 13 screws (3)on top of the engine air
cleaner/filter cover to gain
access to both air
cleaner/filters.
4. Lift the engine air cleaner/filter cover.
5. Lift and remove one or both engine air
cleaner/filters.
{Warning
If part replacement is
necessary, the part must be
replaced with one of the
same part number or with an
equivalent part. Use of a
replacement part without
the same fit, form, and
function may result in
personal injury or damage to
the vehicle.
6. Inspect or replace one or both engine air cleaner/
filters. 7. Reverse Steps 1–4 to
reinstall the engine air
cleaner/filter cover.
8. If equipped, reset the engine air filter life system
after replacing the engine
air filter. See Engine Air
Filter Life System 0383.
Cooling System
The cooling system allows the
engine to maintain the correct
working temperature.
2.0L L4 Engine
1. Engine Coolant Surge
Tank and Pressure Cap
2. Engine Cooling Fan (Out of View)
2.7L L4 Engine
1. Engine Coolant SurgeTank and Pressure Cap
2. Engine Cooling Fan (Out of View)
3. Cooling System Air Bleeder Cap

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 387
3.6L V6 Engine
1. Engine Coolant SurgeTank and Pressure Cap
2. Engine Cooling Fan (Out of View)
{Warning
An underhood electric fan
can start up even when the
engine is not running and
can cause injury. Keep
hands, clothing, and tools
away from any underhood
electric fan.
{Warning
Do not touch heater or
radiator hoses, or other
engine parts. They can be
very hot and can burn you.
Do not run the engine if
there is a leak; all coolant
could leak out. That could
cause an engine fire and can
burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the
vehicle is filled with
DEX-COOL engine coolant.
See Maintenance Schedule
0469 and
Recommended Fluids and
Lubricants 0474.
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, see
Engine Overheating 0391.
What to Use
{Warning
Do not touch heater or
radiator hoses, or other
engine parts. They can be
very hot and can burn you.
Do not run the engine if
there is a leak; all coolant
could leak out. That could
cause an engine fire and can
burn you. Fix any leak before
driving the vehicle.
Use a 50/50 mixture of clean
drinkable water and
DEX-COOL coolant. This
mixture:
.Gives freezing protection
down to −37 °C (−34 °F),
outside temperature.
.Gives boiling protection up
to 129 °C (265 °F), engine
temperature.
.Protects against rust and
corrosion.
.Will not damage aluminum
parts.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
388 Vehicle Care
.Helps keep the proper
engine temperature.
Caution
Do not use anything other
than a mix of DEX-COOL
coolant that meets GM
Standard GMW3420 and
clean, drinkable water.
Anything else can cause
damage to the engine
cooling system and the
vehicle, which would not be
covered by the vehicle
warranty.
Never dispose of engine
coolant by putting it in the
trash, pouring it on the
ground, or into sewers,
streams, or bodies of water.
Have the coolant changed by
an authorized service center,
familiar with legal
requirements regarding used
coolant disposal. This will help
protect the environment and
your health.
Checking Coolant
The vehicle must be on a level
surface when checking the
coolant level.
It is normal to see coolant
moving in the upper coolant
hose return line when the
engine is running. It is also
normal to see bubbles
entering the surge tank
through the small hose.
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 indicated mark, add a
50/50 mixture of clean
drinkable water and
DEX-COOL coolant.
Be sure the cooling system is
cool before this is done.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 389
If no coolant is visible in the
coolant surge tank, add
coolant as follows:
How to Add Coolant to the
Coolant Surge Tank
{Warning
Spilling coolant on hot
engine parts can burn you.
Coolant contains ethylene
glycol and it will burn if the
engine parts are hot enough.
{Warning
Plain water, or other liquids
such as alcohol, can boil
before the proper coolant
mixture will. With plain water
or the wrong mixture, the
engine could get too hot but
there would not be an
overheat warning. The
engine could catch fire and
you or others could be
burned.
{Warning
Steam and scalding liquids
from a hot cooling system
are under pressure. Turning
the pressure cap, even a
little, can cause them to
come out at high speed and
you could be burned. Never
turn the cap when the
cooling system, including the
pressure cap, is hot. Wait for
the cooling system and
pressure cap to cool.
Caution
Failure to follow the specific
coolant fill procedure could
cause the engine to
overheat and could cause
system damage. If coolant is
not visible in the surge tank,
contact your dealer.
If no problem is found, check
to see if coolant is visible in
the coolant surge tank.
If coolant is visible but the coolant level is not at or above
the indicated mark, add a
50/50 mixture of clean,
drinkable water and
DEX-COOL coolant at the
coolant surge tank, but be
sure the cooling system,
including the coolant surge
tank pressure cap, is cool
before you do it.2.0L L4 Engine and 3.6L
V6 Engine
Automatic Coolant Service
Fill Instructions
The vehicle is equipped with a
service feature that assists
with filling and removing air
from the cooling system after
service of components or
when coolant is added after
being to low.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
390 Vehicle Care
To use this feature:
1. With a cold system, addcoolant to the indicated
line on the surge tank.
2. Replace the pressure cap on the surge tank.
3. Activate the service feature:
3.1. Connect the vehicle to a battery charger.
3.2.Turn the ignition to Service Mode. See
Ignition Positions 0261.
3.3.Turn off the air conditioning. 3.4.Set the parking brake.
3.5.At the same time, press
the accelerator and the
brake pedal for
two seconds, then
release.
3.6.At the end of the cycle, check the coolant level
in the surge tank and
add coolant if it is
below the indicated
line. Turn the ignition
off, allow the Electronic
Control Module (ECM)
to go to sleep, about
two minutes, and
repeat Steps 3.2 –3.6.
Listen for pump activation and
movement of the control
valves while watching the level
of the coolant in the surge
tank. If the tank empties, turn
the ignition off, carefully
remove the pressure cap, refill
to the indicated line, replace
the pressure cap, and repeat
steps 3.2 –3.6. The fill and air removal
process will run for
approximately 15 minutes.
Caution
If the pressure cap is not
tightly installed, coolant loss
and engine damage may
occur. Be sure the cap is
properly and tightly secured.
2.7L L4 Engine
Automatic Coolant Service
Fill Instructions
The vehicle is equipped with a
service feature that assists
with filling and removing air
from the cooling system after
service of components or
when coolant is added after
being to low.
To use this feature:
1. With a cold system unscrew the cooling
system air bleeder cap.
If coolant can be seen
through the bleeder move
to Step 3.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 391
2. Add coolant through thesurge tank until it is visible
through the air bleeder.
3. Replace the cooling system air bleeder cap.
4. Add coolant to the indicated line on the
surge tank.
5. Replace the pressure cap on the surge tank.
6. Activate the service feature:
6.1. Connect the vehicle to a battery charger.
6.2.Turn the ignition to Service Mode. See
Ignition Positions 0261.
6.3.Turn off the air conditioning.
6.4.Set the parking brake.
6.5.At the same time, press the accelerator and the
brake pedal for
two seconds, then
release. 6.6.At the end of the cycle,
check the coolant level
in the surge tank and
add coolant if it is
below the indicated
line. Turn the ignition
off, carefully remove
the pressure cap, refill
to the indicated line,
replace the pressure
cap, and repeat steps
6.2 –6.6.
Listen for pump activation and
movement of the control
valves while watching the level
of the coolant in the surge
tank. If the tank empties, turn
the ignition off, carefully
remove the pressure cap, refill
to the indicated line, replace
the pressure cap, and repeat
steps 6.2 –6.6.
The fill and air removal
process will run for
approximately 15 minutes.Caution
If the pressure cap is not
tightly installed, coolant loss
and engine damage may
occur. Be sure the cap is
properly and tightly secured.
Engine Overheating
The vehicle has an indicator to
warn of the engine
overheating.
If the decision is made not to
lift the hood when this
warning appears, get service
help right away. See Roadside
Assistance Program 0487.
If the decision is made to lift
the hood, make sure the
vehicle is parked on a level
surface.
Then check to see if the
engine cooling fan is running.
If the engine is overheating,
the fan should be running. If it
is not, do not continue to run
the engine. Have the vehicle
serviced.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
392 Vehicle Care
Caution
Do not run the engine if
there is a leak in the engine
cooling system. This can
cause a loss of all coolant
and can damage the system
and vehicle. Have any leaks
fixed right away.
If Steam Is Coming from
the Engine Compartment
{Warning
Steam and scalding liquids
from a hot cooling system
are under pressure. Turning
the pressure cap, even a
little, can cause them to
come out at high speed and
you could be burned. Never
turn the cap when the
cooling system, including the
pressure cap, is hot. Wait for
the cooling system and
pressure cap to cool.
If No Steam Is Coming
from the Engine
Compartment
If an engine overheat warning
is displayed but no steam can
be seen or heard, the problem
may not be too serious.
Sometimes the engine can get
a little too hot when the
vehicle:
.Climbs a long hill on a
hot day.
.Stops after high-speed
driving.
.Idles for long periods in
traffic.
If the overheat warning is
displayed with no sign of
steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and
to the highest fan speed.
Open the windows as
necessary. 3. When it is safe to do so,
pull off the road, shift to
P (Park) or N (Neutral) and
let the engine idle.
If the overheat warning no
longer displays, the vehicle
can be driven. Continue to
drive the vehicle slowly for
about 10 minutes. Keep a safe
vehicle distance from the
vehicle in front. If the warning
does not come back on,
continue to drive normally and
have the cooling system
checked for proper fill and
function.
If the warning continues, pull
over, stop, and park the
vehicle right away.
If there is no sign of steam,
idle the engine for
three minutes while parked.
If the warning is still displayed,
turn off the engine until it
cools down.