check engine BUICK REGAL 2018 Owner's Guide

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
11486030) - 2018 - crc - 3/23/18
238 Driving and Operating
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) 0133. A device connected
to the DLC —such as an
aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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240 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 241
California Proposition65 Warning . . . . . . . . . . . . . . . . . 241
California Perchlorate Materials Requirements . . . . . 242
Accessories and Modifications . . . . . . . . . . . . . . . . 242
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 242
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 243
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 244
Engine Oil . . . . . . . . . . . . . . . . . . . . 247
Engine Oil Life System . . . . . . . 249
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 250
Engine Air Cleaner/Filter . . . . . . 251
Cooling System . . . . . . . . . . . . . . 252
Engine Overheating . . . . . . . . . . 256
Washer Fluid . . . . . . . . . . . . . . . . . 257
Brakes . . . . . . . . . . . . . . . . . . . . . . . 258
Brake Fluid . . . . . . . . . . . . . . . . . . . 259
Battery - North America . . . . . . 260
All-Wheel Drive . . . . . . . . . . . . . . . 261 Starter Switch Check . . . . . . . . . 261
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 261
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 261
Wiper Blade Replacement . . . . 262
Windshield Replacement . . . . . 263
Gas Strut(s) . . . . . . . . . . . . . . . . . . 263
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 264
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 265
Halogen Bulbs . . . . . . . . . . . . . . . . 265
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 265
Headlamps . . . . . . . . . . . . . . . . . . . 265
Fog Lamps . . . . . . . . . . . . . . . . . . . 266
Front Turn Signal Lamps . . . . . 266
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 266
Electrical System
Electrical System Overload . . . 267
Fuses and Circuit Breakers . . . 268
Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 268 Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 272
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 274
All-Season Tires . . . . . . . . . . . . . . 275
Winter Tires . . . . . . . . . . . . . . . . . . 275
Low-Profile Tires . . . . . . . . . . . . . 275
Tire Sidewall Labeling . . . . . . . . 276
Tire Designations . . . . . . . . . . . . . 278
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 278
Tire Pressure . . . . . . . . . . . . . . . . . 281
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 282
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 283
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 284
Tire Inspection . . . . . . . . . . . . . . . . 287
Tire Rotation . . . . . . . . . . . . . . . . . 287
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 288
Buying New Tires . . . . . . . . . . . . . 289
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 290
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 291
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 292
Wheel Replacement . . . . . . . . . . 293

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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Vehicle Care 247
1. Windshield Washer FluidReservoir. See Washer Fluid
0 257.
2. Engine Oil Fill Cap. See Engine Oil 0247.
3. Engine Oil Dipstick. See Engine Oil 0247.
4. Engine Cooling Fans (Out of View). See Cooling System
0 252
5. Brake Fluid Reservoir. See Brake Fluid 0259.
6. Engine Air Cleaner/Filter 0251.
7. Coolant Surge Tank and Pressure Cap. See Cooling
System 0252.
8. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0315.
9. Engine Compartment Fuse
Block 0268.
10. Remote Negative (-) Ground Terminal. See Jump Starting -
North America 0315.Engine Oil
To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil”
in this section.
. Check the engine oil level
regularly and maintain the
proper oil level. See “Checking
Engine Oil” and“When to Add
Engine Oil” in this section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0249.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially
prior to a long trip. The engine oil
dipstick handle is a loop. See
Engine Compartment Overview
0244 for the location.
{Warning
The engine oil dipstick handle
may be hot; it could burn you.
Use a towel or glove to touch the
dipstick handle.
If a low oil Driver Information Center
(DIC) message displays, check the
oil level.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground.
Check the engine oil level after
the engine has been off for at
least two hours. Checking the
engine oil level on steep grades
or too soon after engine shutoff
can result in incorrect readings.
Accuracy improves when

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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248 Vehicle Care
checking a cold engine prior to
starting. Remove the dipstick
and check the level.
. If unable to wait two hours, the
engine must be off for at least
15 minutes if the engine is
warm, or at least 30 minutes if
the engine is not warm. Pull out
the dipstick, wipe it with a clean
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 Shown, L4 Engine
Similar
If the oil is below the cross-hatched
area at the tip of the dipstick and
the engine has been off for at least 15 minutes, add 1 L (1 qt) of the
recommended oil and then recheck
the level. See
“Selecting the Right
Engine Oil” later in this section for
an explanation of what kind of oil to
use. For engine oil crankcase
capacity, see Capacities and
Specifications 0344.
Caution
Do not add too much oil. Oil
levels above or below the
acceptable operating range
shown on the dipstick are harmful
to the engine. If you find that you
have an oil level above the
operating range, i.e., the engine
has so much oil that the oil level
gets above the cross-hatched
area that shows the proper
operating range, the engine could
be damaged. You should drain
out the excess oil or limit driving
of the vehicle and seek a service
professional to remove the
excess amount of oil. See
Engine Compartment Overview
0 244 for the location of the engine
oil fill cap.
Add enough oil to put the level
somewhere in the proper operating
range. Push the dipstick all the way
back in when through.
Selecting the Right Engine Oil
Selecting the right engine oil
depends on both the proper oil
specification and viscosity grade.
See Recommended Fluids and
Lubricants 0340.
Specification
Use full synthetic engine oils that
meet the dexos1 specification.
Engine oils that have been
approved by GM as meeting the
dexos1 specification are marked
with the dexos1 approved logo. See
www.gmdexos.com.

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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250 Vehicle Care
When the system has calculated
that oil life has been diminished, it
indicates that an oil change is
necessary. A CHANGE ENGINE
OIL SOON message comes on.
Change the oil as soon as possible
within the next 1 000 km (600 mi).
It is possible that, if driving under
the best conditions, the oil life
system may indicate that an oil
change is not necessary for up to a
year. The engine oil and filter must
be changed at least once a year
and at this time the system must be
reset. Your dealer has trained
service people who will perform this
work and reset the system. It is also
important to check the oil regularly
over the course of an oil drain
interval and keep it at the proper
level.
If the system is ever reset
accidentally, the oil must be
changed at 5 000 km (3,000 mi)
since the last oil change.
Remember to reset the oil life
system whenever the oil is changed.How to Reset the Engine Oil
Life System
Reset the system whenever the
engine oil is changed so that the
system can calculate the next
engine oil change. To reset the
system:1. Using the DIC controls on the right side of the steering wheel,
display REMAINING OIL LIFE
on the DIC. See Driver
Information Center (DIC) 0141.
When remaining oil life is low,
the CHANGE ENGINE OIL
SOON message will appear on
the display.
2. Press
Von the DIC controls
and hold down for a few
seconds to clear the CHANGE
ENGINE OIL SOON message
and reset the oil life at 100%.
Be careful not to reset the oil
life display accidentally at any
time other than after the oil is
changed. It cannot be reset
accurately until the next oil
change. The system is reset when the
CHANGE ENGINE OIL SOON
message is off.
If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started, the engine oil life
system has not been reset. Repeat
the procedure.
Automatic Transmission
Fluid
How to Check Automatic
Transmission Fluid
It is not necessary to check the
transmission fluid level.
A transmission fluid leak is the only
reason for fluid loss. If a leak
occurs, take the vehicle to your
dealer and have it repaired as soon
as possible.
There is a special procedure for
checking and changing the
transmission fluid. Because this
procedure is difficult, you should
have this done at your dealer.
Contact your dealer for additional
information. The procedure can be

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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Vehicle Care 253
3.6L V6 Engine
1. Engine Cooling Fans (Outof View)
2. Coolant Surge Tank and Pressure Cap
{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. This coolant is designed to
remain in the vehicle for five years
or 240 000 km (150,000 mi),
whichever occurs first.
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 0256.
What to Use
{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.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. If using this mixture,
nothing else needs to be added.
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.

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
11486030) - 2018 - crc - 3/23/18
254 Vehicle Care
.Will not damage aluminum parts.
. 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.
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 mark
pointed to, add a 50/50 mixture of
clean, drinkable water and
DEX-COOL coolant. Be sure the cooling system is cool
before this is done.
If no coolant is visible in the coolant
surge tank, add coolant as follows:
How to Add Coolant to the
Coolant Surge Tank
{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.
{Warning
Plain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
(Continued)

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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Vehicle Care 255
Warning (Continued)
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
Spilling coolant on hot engine
parts can burn you. Coolant
contains ethylene glycol and it will
burn if the engine parts are hot
enough.
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 the
indicated level 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.
1. Remove the coolant surge tank
pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is 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 will allow any
pressure still left to be vented
out the discharge hose.
2. Keep turning the pressure cap slowly and remove it.3. Fill the coolant surge tank withthe proper mixture to the
indicated level mark.
4. With the coolant surge tank pressure cap off, start the
engine and let it run until you
can feel the upper radiator
hose getting hot. Watch out for
the engine cooling fans.

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
11486030) - 2018 - crc - 3/23/18
256 Vehicle Care
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge
tank until the level reaches the
indicated level mark.
5. Replace the pressure cap tightly.
Check the level in the coolant surge
tank when the cooling system has
cooled down. If the coolant is not at
the proper level, repeat Steps 1–
3 and reinstall the pressure cap.
If the coolant still is not at the proper
level when the system cools down
again, see your dealer.
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 engine coolant
temperature gauge and an engine
coolant temperature warning light on
the instrument cluster to warn of
engine overheating.
See Engine Coolant Temperature
Gauge 0130 and Engine Coolant
Temperature Warning Light 0138.
If it is decided not to lift the hood
when this warning appears, but
instead get service help right away,
see Roadside Assistance Program
0 350.
If it is decided 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.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.

Buick Regal Owner Manual (GMNA-Localizing-2nd Timed Print-U.S./Canada-
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Vehicle Care 257
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 engine coolant temperature
gauge is no longer in the overheat
zone or the engine coolant
temperature warning light 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.
Washer Fluid
What to Use
When windshield washer fluid is
needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an
area where the temperature may fall
below freezing, use a fluid that has
sufficient protection against
freezing.
Adding Washer Fluid
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. See
Engine
Compartment Overview 0244 for
reservoir location.
Caution
. Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
. Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
(Continued)