engine BUICK ENCORE GX 2021 Repair Manual

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608036) - 2021 - CRC - 9/21/20
238 Driving and Operating
To turn LKA on and off, pressAon the
center console. If equipped, the indicator
light on the button comes on when LKA is
on and turns off when LKA is disabled.
When on,
Ais white, if equipped,
indicating that the system is not ready to
assist.
Ais green if LKA is ready to
assist. LKA may assist by gently turning the
steering wheel if the vehicle approaches a
detected lane marking.
Ais amber when
assisting. It may also provide a Lane
Departure Warning (LDW) alert by flashing
Aamber if the vehicle crosses a
detected lane marking. Additionally, there
may be three beeps on the right or left,
depending on the lane departure direction.
Take Steering
The LKA system does not continuously steer
the vehicle. If LKA does not detect active
driver steering, an alert and chime may be
provided. Steer the vehicle to dismiss. LKA
may become temporarily unavailable after
repeated take steering alerts.
When the System Does Not Seem to
Work Properly
The system performance may be
affected by:
.Close vehicles ahead.
.Sudden lighting changes, such as when
driving through tunnels.
.Banked roads.
.Roads with poor lane markings, such as
two-lane roads.
If the LKA system is not functioning
properly when lane markings are clearly
visible, cleaning the windshield may help.
A camera blocked message may display if
the camera is blocked. Some driver
assistance systems may have reduced
performance or not work at all. An LKA or
LDW unavailable message may display if the
systems are temporarily unavailable. This
message could be due to a blocked camera.
The LKA system does not need service. Clean
the outside of the windshield behind the
rearview mirror.
LKA assistance and/or LDW alerts may occur
due to tar marks, shadows, cracks in the
road, temporary or construction lane
markings, or other road imperfections. This
is normal system operation; the vehicle does
not need service. Turn LKA off if these
conditions continue.
Fuel
Top Tier Fuel
GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine clean,
reduce engine deposits, and maintain
optimal vehicle performance. Look for the
TOP TIER Logo or see www.toptiergas.com
for a list of TOP TIER Detergent Gasoline
marketers and applicable countries.

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608036) - 2021 - CRC - 9/21/20
Driving and Operating 239
Recommended Fuel
Use regular unleaded gasoline meeting
ASTM specification D4814 with a posted
octane rating of 87—(R+M)/2 —or higher.
Do not use gasoline with a posted octane
rating of less than 87, as this may cause
engine knock and will lower fuel economy.
Do not use any fuel labeled E85 or FlexFuel.
Do not use gasoline with ethanol levels
greater than 15% by volume.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so may
damage the vehicle and void its
warranty:
(Continued)
Caution (Continued)
.For vehicles that are not FlexFuel, fuel
labeled greater than 15% ethanol by
volume, such as mid-level ethanol
blends (16–50% ethanol), E85,
or FlexFuel.
.Fuel with any amount of methanol,
methylal, ferrocene, and aniline. These
fuels can corrode metal fuel system
parts or damage plastic and rubber
parts.
.Fuel containing metals such as
methylcyclopentadienyl manganese
tricarbonyl (MMT), which can damage
the emissions control system and
spark plugs.
.Fuel with a posted octane rating of
less than the recommended fuel. Using
this fuel will lower fuel economy and
performance, and may decrease the
life of the emissions catalyst.
Fuels in Foreign Countries
The U.S., Canada, and Mexico post fuel
octane ratings in anti-knock index (AKI). For
fuel not to use in a foreign country, see
Prohibited Fuels 0239.
Fuel Additives
TOP TIER Detergent Gasoline is highly
recommended for use with your vehicle.
If your country does not have TOP TIER
Detergent Gasoline, add ACDelco Fuel
System Treatment Plus−Gasoline to the
vehicle’s gasoline fuel tank at every oil
change or 15 000 km (9,000 mi), whichever
occurs first. TOP TIER Detergent Gasoline and
ACDelco Fuel System Treatment Plus
−Gasoline will help keep your vehicle’s
engine fuel deposit free and performing
optimally.
Filling the Tank
An arrow on the fuel gauge indicates which
side of the vehicle the fuel door is on. See
Fuel Gauge 094.
{Warning
Fuel vapors and fuel fires burn violently
and can cause injury or death.
Follow these guidelines to help avoid
injuries to you and others:
.Read and follow all the instructions on
the fuel pump island.
(Continued)

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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240 Driving and Operating
Warning (Continued)
.Turn off the engine when refueling.
.Keep sparks, flames, and smoking
materials away from fuel.
.Do not leave the fuel pump
unattended.
.Avoid using electronic devices while
refueling.
.Do not re-enter the vehicle while
pumping fuel.
.Keep children away from the fuel
pump and never let children
pump fuel.
.Before touching the fill nozzle, touch a
metallic object to discharge static
electricity from your body.
.Fuel can spray out if the fill nozzle is
inserted too quickly. This spray can
happen if the tank is nearly full, and is
more likely in hot weather. Insert the
fill nozzle slowly and wait for any hiss
noise to stop before beginning to
flow fuel.
To open the fuel door, push and release the
rearward center edge of the door.
The capless refueling system does not have
a fuel cap. Fully insert and latch the fill
nozzle, then begin fueling.
{Warning
Overfilling the fuel tank by more than
three clicks of a standard fill nozzle may
cause:
.Vehicle performance issues, including
engine stalling and damage to the fuel
system.
.Fuel spills.
.Under certain conditions, fuel fires.Be careful not to spill fuel. Wait five seconds
after you have finished pumping before
removing the fill nozzle. Clean fuel from
painted surfaces as soon as possible. See
Exterior Care
0314. Push the fuel door
closed until it latches.
{Warning
If a fire starts while you are refueling, do
not remove the fill nozzle. Shut off the
flow of fuel by shutting off the pump or
by notifying the station attendant. Leave
the area immediately.
Filling the Tank with a Portable Fuel
Container
If the vehicle runs out of fuel and must be
filled from a portable fuel container:
1. Locate the capless funnel adapter from the rear cargo area under the load
floor tray.

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608036) - 2021 - CRC - 9/21/20
242 Driving and Operating
The following information has many
time-tested, important trailering tips and
safety rules. Many of these are important
for your safety and that of your passengers.
Read this section carefully before pulling a
trailer.
When towing a trailer:
.Become familiar with and follow all state
and local laws that apply to trailer
towing. These requirements vary from
state to state.
.State laws may require the use of
extended side view mirrors. Even if not
required, you should install extended side
view mirrors if your visibility is limited or
restricted while towing.
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to
prevent damage to the engine, axle,
or other parts.
.It is recommended to perform the first oil
change before heavy towing.
.During the first 800 km (500 mi) of
trailer towing, do not drive over 80 km/h
(50 mph) and do not make starts at full
throttle.
.Vehicles can tow in D (Drive). If the
transmission downshifts too often, a
lower gear may be selected using Manual
Mode SeeManual Mode 0207.
If equipped, the following driver assistance
features should be turned off when towing
a trailer:
.Adaptive Cruise Control (ACC)
.Super Cruise Control
.Lane Keep Assist (LKA)
.Park Assist
.Automatic Parking Assist (APA)
.Reverse Automatic Braking (RAB)
If equipped, the following driver assistance
features should be turned to alert or off
when towing a trailer:
.Automatic Emergency Braking (AEB)
.Intelligent Brake Assist (IBA)
.Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert (LCA),
the LCA detection zones that extend back
from the side of the vehicle do not move
further back when a trailer is towed. Use
caution while changing lanes when towing a
trailer. If equipped with Rear Cross Traffic Alert
(RCTA), use caution while backing up when
towing a trailer, as the RCTA detection zones
that extend out from the back of the vehicle
do not move further back when a trailer is
towed.
{Warning
To prevent serious injury or death from
carbon monoxide (CO), when towing a
trailer:
.Do not drive with the liftgate, trunk/
hatch, or rear-most window open.
.Fully open the air outlets on or under
the instrument panel.
.Adjust the climate control system to a
setting that brings in only outside air.
See
“Climate Control Systems” in the
Index.
For more information about carbon
monoxide, see Engine Exhaust 0204.

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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244 Driving and Operating
Driving on Grades
Reduce speed and shift to a lower gear
before starting down a long or steep
downhill grade. If the transmission is not
shifted down, the brakes may overheat and
result in reduced braking efficiency.
The vehicle can tow in D (Drive). Shift the
transmission to a lower gear if the
transmission shifts too often under heavy
loads and/or hilly conditions.
When towing at higher altitudes, engine
coolant will boil at a lower temperature
than at lower altitudes. If the engine is
turned off immediately after towing at high
altitude on steep uphill grades, the vehicle
could show signs similar to engine
overheating. To avoid this, let the engine
run, preferably on level ground, with the
transmission in P (Park) for a few minutes
before turning the engine off. If the
overheat warning comes on, seeEngine
Overheating 0266.
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and trailer on a
level surface when possible.
When parking your vehicle and your trailer
on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the wheels into
the curb if facing downhill or into traffic
if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, gradually release the brake pedal to
allow the chocks to absorb the load of
the trailer.
4. Reapply the brake pedal. Then apply the parking brake and shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
.Shift into a gear.
.Release the parking brake.
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
The vehicle needs service more often when
used to tow trailers. See Maintenance
Schedule 0323. It is especially important to
check the automatic transmission fluid,
engine oil, axle lubricant, belts, cooling
system, and brake system before and during
each trip.
Check periodically that all nuts and bolts on
the trailer hitch are tight.

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 245
Engine Cooling When Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
SeeEngine Overheating 0266.
Trailer Towing
Caution
Towing a trailer improperly can damage
the vehicle and result in costly repairs
not covered by the vehicle warranty. To
tow a trailer correctly, follow the
directions in this section and see your
dealer for important information about
towing a trailer with the vehicle.
Trailer Weight
{Warning
Never exceed the towing capacity for
your vehicle.
Safe trailering requires monitoring the
weight, speed, altitude, road grades, outside
temperature, dimensions of the front of the
trailer, and how frequently the vehicle is
used to tow a trailer.
Trailer Weight Ratings
When towing a trailer, the weight of the
loaded vehicle and trailer must be within
the weight ratings for the vehicle.
.GCWR: Gross Combined Weight Rating
.GVWR: Gross Vehicle Weight Rating
.Maximum Trailer Weight Rating
.Maximum Trailer Tongue Weight
See “Weight-Distributing Hitch Adjustment”
under Towing Equipment 0248 to
determine if equalizer bars are required to
obtain the maximum trailer weight rating.
See “Trailer Brakes” underTowing
Equipment 0248 to determine if brakes are
required based on your trailer's weight.
The only way to be sure the weight is not
exceeding any of these ratings is to weigh
the tow vehicle and trailer combination,
fully loaded for the trip, getting individual
weights for each of these items.
{Warning
You and others could be seriously injured
or killed if the trailer is too heavy or the
trailer brakes are inadequate for the load.
The vehicle may be damaged, and the
repairs would not be covered by the
vehicle warranty.
Only tow a trailer if all the steps in this
section have been followed. Ask your
dealer for advice and information about
towing a trailer.
Gross Combined Weight Rating (GCWR)
GCWR is the total allowable weight of the
completely loaded vehicle and trailer
including any fuel, passengers, cargo,
equipment, and accessories. Do not exceed
the GCWR for your vehicle. The GCWR for
the vehicle is on the tow rating chart later
in this section.

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 249
Cross the safety chains under the tongue of
the trailer to help prevent the tongue from
contacting the road if it becomes separated
from the hitch. Always leave just enough
slack so the combination can turn. Never
allow safety chains to drag on the ground.
Trailer Brakes
Loaded trailers over 450 kg (1,000 lb) must
be equipped with brake systems and with
brakes for each axle. Trailer braking
equipment conforming to Canadian
Standards Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may require
trailers to have their own braking system if
the loaded weight of the trailer exceeds
certain minimums that can vary from state
to state. Read and follow the instructions for
the trailer brakes so they are installed,
adjusted, and maintained properly. Never
attempt to tap into your vehicle's hydraulic
brake system. If you do, both the vehicle
anti-lock brakes and the trailer brakes may
not function, which could result in a crash.
Trailer Lamps
Always check all trailer lamps are working at
the beginning of each trip, and periodically
on longer trips.
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals should will illuminate to indicate the
vehicle is turning, changing lanes,
or stopping. When towing a trailer, the
arrows on the instrument cluster will
illuminate even if the trailer is not properly
connected or the bulbs are burned out.
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to
support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection.
Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blow-outs.Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old.
Overloading is another leading cause of
trailer tire blow-outs. Never load your trailer
with more weight than the tires are
designed to support. The load rating is
located on the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be on
the trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. See
Malfunction
Indicator Lamp (Check Engine Light) 097.
(Continued)

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 251
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 252
California Proposition 65 Warning . . . . . 252
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 252
Accessories and Modifications . . . . . . . . . 252
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 253
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Engine Compartment Overview . . . . . . . . 255
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Engine Oil Life System . . . . . . . . . . . . . . . . 260
Automatic Transmission Fluid . . . . . . . . . 260
Engine Air Filter Life System . . . . . . . . . . 260
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 261
Cooling System . . . . . . . . . . . . . . . . . . . . . . . 262
Engine Overheating . . . . . . . . . . . . . . . . . . . 266
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
Brake Pad Life System . . . . . . . . . . . . . . . . 268
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Battery - North America . . . . . . . . . . . . . . . 270
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . 272
Automatic Transmission Shift Lock Control Function Check . . . . . . . . . . . . . . 272
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272 Wiper Blade Replacement . . . . . . . . . . . . . 272
Windshield Replacement . . . . . . . . . . . . . . . 273
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . 274
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 274
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 275
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 275
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
Headlamps and Sidemarker Lamps . . . . . 275
Front Turn Signal and Fog Lamps . . . . . . 276
Taillamps, Turn Signal, Sidemarker,
Stoplamps, and Back-Up Lamps (Base
Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
Taillamps, Turn Signal, Sidemarker, Stoplamps, and Back-Up Lamps
(Uplevel) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
Electrical System
Electrical System Overload . . . . . . . . . . . . 280
Fuses and Circuit Breakers . . . . . . . . . . . . . 281
Engine Compartment Fuse Block . . . . . . . 281
Instrument Panel Fuse Block . . . . . . . . . . 284
Rear Compartment Fuse Block . . . . . . . . . 285
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 287
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 288 Tire Designations . . . . . . . . . . . . . . . . . . . . . . 289
Tire Terminology and Definitions . . . . . 290
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 292
Tire Pressure Monitor System . . . . . . . . . 293
Tire Pressure Monitor Operation . . . . . . 294
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 297
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 297
When It Is Time for New Tires . . . . . . . . 298
Buying New Tires . . . . . . . . . . . . . . . . . . . . . 299
Different Size Tires and Wheels . . . . . . . 300
Uniform Tire Quality Grading . . . . . . . . . 300
Wheel Alignment and Tire Balance . . . . 302
Wheel Replacement . . . . . . . . . . . . . . . . . . . 302
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 303
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 304
Compact Spare Tire . . . . . . . . . . . . . . . . . . . 308
Jump Starting
Jump Starting - North America . . . . . . . . 308
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . . 311
Recreational Vehicle Towing . . . . . . . . . . . . 311
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320

Buick Encore GX Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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252 Vehicle Care
General Information
For service and parts needs, visit your
dealer. You will receive genuine GM parts
and GM-trained and supported service
people.
Genuine GM parts have one of these marks:
California Proposition 65 Warning
{Warning
Most motor vehicles, including this one,
as well as many of its service parts and
fluids, contain and/or emit chemicals
known to the State of California to cause(Continued)
Warning (Continued)
cancer and birth defects or other
reproductive harm. Engine exhaust, many
parts and systems, many fluids, and
some component wear by-products
contain and/or emit these chemicals. For
more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0270 and
Jump Starting - North America 0308 and
the back cover.
California Perchlorate Materials
Requirements
Certain types of automotive applications,
such as airbag initiators, seat belt
pretensioners, and lithium batteries
contained in electronic keys, may contain
perchlorate materials. Perchlorate Material –
special handling may apply. See
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and Modifications
Adding non-dealer accessories or making
modifications to the vehicle can affect
vehicle performance and safety, including
such things as airbags, braking, stability,
ride and handling, emissions systems,
aerodynamics, durability, and electronic
systems like antilock brakes, traction control,
and stability control. These accessories or
modifications could even cause malfunction
or damage not covered by the vehicle
warranty.
Damage to suspension components caused
by modifying vehicle height outside of
factory settings will not be covered by the
vehicle warranty.
Damage to vehicle components resulting
from modifications or the installation or use
of non-GM certified parts, including control
module or software modifications, is not
covered under the terms of the vehicle
warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement
and function with other systems on the
vehicle. See your dealer to accessorize the
vehicle using genuine GM Accessories
installed by a dealer technician.

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Vehicle Care 253
Also, seeAdding Equipment to the
Airbag-Equipped Vehicle 059.
Vehicle Checks
Doing Your Own Service Work
{Warning
It can be dangerous to work on your
vehicle if you do not have the proper
knowledge, service manual, tools,
or parts. Always follow owner’s manual
procedures and consult the service
manual for your vehicle before doing any
service work.
If doing some of your own service work, use
the proper service manual. It tells you much
more about how to service the vehicle than
this manual can. To order the proper service
manual, see Publication Ordering
Information 0346.
This vehicle has an airbag system. Before
attempting to do your own service work,
see Servicing the Airbag-Equipped Vehicle
0 59. If equipped with remote vehicle start, open
the hood before performing any service
work to prevent remote starting the vehicle
accidentally. See
Remote Vehicle Start 013.
Keep a record with all parts receipts and list
the mileage and the date of any service
work performed. See Maintenance Records
0 334.Caution
Even small amounts of contamination can
cause damage to vehicle systems. Do not
allow contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
{Warning
For vehicles with auto engine stop/start,
turn the vehicle off before opening the
hood. If the vehicle is on, the engine will
start when the hood is opened. You or
others could be injured.
{Warning
Components under the hood can get hot
from running the engine. To help avoid
the risk of burning unprotected skin,
never touch these components until they
have cooled, and always use a glove or
towel to avoid direct skin contact.
Clear any snow from the hood before
opening.
To open the hood:
1. Pull the hood release handle inside the vehicle. It is located on the lower left
side of the instrument panel.