2020 Hyundai Sonata check engine

Maintenance8-6
While operating your vehicle:
• Note any changes in the sound of the exhaust or any smell of exhaust fumes
in the vehicle.
• Check for vibrations in the steering wheel. Notice if there is any increased
steering effort or looseness in the
steering wheel, or change in its
straight-ahead position.
• Notice if your vehicle constantly turns slightly or “pulls” to one side when
traveling on smooth, level road.
• When stopping, listen and check for unusual sounds, pulling to one side,
increased brake pedal travel or “hard-
to-push” brake pedal.
• If any slipping or changes in the operation of your transmission occurs,
check the transmission fluid level.
• Check the automatic transmission P (Park) function.
• Check the parking brake.
• Check for fluid leaks under your vehicle (water dripping from the air
conditioning system during or after
use is normal).
At least monthly:
• Check coolant level in the engine coolant reservoir.
• Check the operation of all exterior lights, including the brake lights, turn
signals and hazard warning flashers.
• Check the inflation pressures of all tires including the spare for tires that
are worn, show uneven wear, or are
damaged.
• Check for loose wheel lug nuts.
At least twice a year:
(i.e., every Spring and Autumn)
• Check radiator, heater and air conditioning hoses for leaks or
damage.
• Check windshield washer spray and wiper operation. Clean wiper blades
with a clean cloth dampened with
washer a fluid.
• Check headlamp alignment.
• Check muffler, exhaust pipes, shields and clamps.
• Check the seat belts for wear and function.
At least once a year:
• Clean body and door drain holes.
• Lubricate door hinges and hood hinges.
• Lubricate door and hood locks and latches.
• Lubricate door rubber weather strips.
• Lubricate door checker.
• Check the air conditioning system.
• Inspect and lubricate automatic transmission linkage and controls.
• Clean the battery and terminals.
• Check the brake fluid level.

Maintenance8-16
Engine Oil and Filter
The engine oil and filter should be
changed at the intervals specified in the
maintenance schedule. If the vehicle
is being driven in severe conditions,
more frequent oil and filter changes are
required.
Drive Belts
Inspect all drive belts for evidence
of cuts, cracks, excessive wear or oil
saturation and replace if necessary. Drive
belts should be checked periodically
for proper tension and adjusted as
necessary.
Fuel Filter
A clogged-up fuel filter may limit the
vehicle driving speed, damage the
emission system, and cause the hard
starting. When a considerable amount
of foreign substances are accumulated
in the fuel tank, the fuel filter should be
replaced.
Upon installing a new fuel filter, operate
the engine for several minutes, and
check the connections for any leakages.
Fuel filters should be installed by an
authorized HYUNDAI dealer.
Fuel Lines, Fuel Hoses and
Connections
Check the fuel lines, fuel hoses and
connections for leakage and damage.
Have an authorized HYUNDAI dealer
replace any damaged or leaking parts
immediately.
Vapor Hose and Fuel Filler Cap
The vapor hose and fuel filler cap should
be inspected at those intervals specified
in the maintenance schedule. Make sure
a new vapor hose or fuel filler cap is
correctly replaced.
Air Cleaner Filter
A genuine HYUNDAI air cleaner filter
is recommended when the filter is
replaced.
Spark Plugs
Make sure to install new spark plugs of
the correct heat range.
Cooling System
Check cooling system components, such
as radiator, coolant reservoir, hoses and
connections for leakage and damage.
Replace any damaged parts.
EXPLANATION OF SCHEDULED MAINTENANCE ITEMS

08
8-17
Engine Coolant
The coolant should be changed at the
intervals specified in the maintenance
schedule.
Automatic Transmission Fluid
Automatic transmission fluid should
not be checked under normal usage
conditions. But in severe conditions, the
fluid should be changed at an authorized
HYUNDAI dealer in accordance to the
scheduled maintenance at the beginning
of this chapter.
Information
Automatic transmission fluid color is red
when new.
As the vehicle is driven, the automatic
transmission fluid will begin to look
darker. This is a normal condition and you
should not judge the need to replace the
fluid based upon the changed color.
NOTICE
The use of a non-specified fluid could
result in transmission malfunction
and failure. Use only the specified
automatic transmission fluid (refer
to “Recommended Lubricants and
Capacities” in chapter 2).
Brake Hoses and Lines
Visually check for proper installation,
chafing, cracks, deterioration and any
leakage. Replace any deteriorated or
damaged parts immediately.
Brake Fluid
Check the brake fluid level in the brake
fluid reservoir. The level should be
between the MIN and the MAX marks
on the side of the reservoir. Use only
hydraulic brake fluid conforming to DOT
4 specification.
Parking Brake
Inspect the parking brake system
including the parking brake pedal and
cables.
Brake Discs, Pads, Calipers and
Rotors
Check the pads for excessive wear, discs
for run out and wear, and calipers for
fluid leakage.
Exhaust Pipe and Muffler
Visually inspect the exhaust pipes,
muffler and hangers for cracks,
deterioration, or damage. Start
the engine and listen carefully for
any exhaust gas leakage. Tighten
connections or replace parts as
necessary.

Maintenance8-18
Suspension Mounting Bolts
Check the suspension connections for
looseness or damage. Retighten to the
specified torque.
Steering Gear Box, Linkage &
Boots/Lower Arm Ball Joint
With the vehicle stopped and the engine
off, check for excessive freeplay in the
steering wheel. Check the linkage for
bends or damage. Check the dust boots
and ball joints for deterioration, cracks,
or damage.
Replace any damaged parts.
Drive Shafts and Boots
Check the drive shafts, boots and clamps
for cracks, deterioration, or damage.
Replace any damaged parts and, if
necessary, repack the grease.
Air Conditioning Refrigerant
Check the air conditioning lines and
connections for leakage and damage.

08
8-19
Checking the Engine Oil Level
1. Follow all of the oil manufacturer’s precautions.
2. Be sure the vehicle is on the level ground in P (Park) with the parking
brake set. If possible, block the
wheels.
3. Turn the engine on and allow the engine to reach normal operating
temperature.
4. Turn the engine off and wait about five minutes for the oil to return to the
oil pan.
5. Pull the dipstick out, wipe it clean, and re-insert it fully.
Smartstream G1.6 T-GDiSmartstream G1.6 T-GDi
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Smartstream G2.5 GDiSmartstream G2.5 GDi
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6. Pull the dipstick out again and check the level. The level should be between
F and L.
Smartstream G1.6 T-GDiSmartstream G1.6 T-GDi
ODN8089105ODN8089105
Smartstream G2.5 GDiSmartstream G2.5 GDi
ODN8089003ODN8089003
7. If it is near or at L, add enough oil to bring the level to F.
Use only the specified engine oil. (refer
to “Recommended Lubricants and
Capacities” in chapter 2).
NOTICE
To prevent damage to your engine:
• Do not overfill with engine oil. Add oil
in small quantities and recheck level
to ensure engine is not overfilled.
• Do not spill engine oil when adding
or changing engine oil. Use a funnel
to help prevent oil from being spilled
on engine components. Wipe off
spilled oil immediately.
ENGINE OIL

Maintenance8-20
Checking the Engine Oil and
Filter
Have engine oil and filter changed by an
authorized HYUNDAI dealer according
to the Maintenance Schedule at the
beginning of this chapter.
WARNING
CALIFORNIA PROPOSITION 65
WARNING
Engine oil contains chemicals known to
the State of California to cause cancer,
birth defects and reproductive harm.
Used engine oil may cause irritation or
cancer of the skin if left in contact with
the skin for prolonged periods of time.
Always protect your skin by washing
your hands thoroughly with soap and
warm water as soon as possible after
handling used oil.

08
8-21
The high-pressure cooling system has a
reservoir filled with year-round antifreeze
coolant. The reservoir is filled at the
factory.
Check the antifreeze protection and
coolant level at least once a year, at
the beginning of the winter season and
before traveling to a colder climate.
NOTICE
• When the engine overheats from
low engine coolant, suddenly adding
engine coolant may cause cracks
in the engine. To prevent damage,
add engine coolant slowly in small
quantities.
• Do not drive with no engine coolant.
It may cause water pump failure and
engine seizure, etc.
Checking the Engine Coolant
Level
ODN8089004ODN8089004
Check the condition and connections
of all cooling system hoses and
heater hoses. Replace any swollen or
deteriorated hoses.
The coolant level should be filled
between the F and the L marks on the
side of the coolant reservoir when the
engine is cool. If the coolant level is low, add enough
distilled (deionized) water to bring the
level to the F mark, but do not overfill. If
frequent additions are required, see an
authorized HYUNDAI dealer for a cooling
system inspection.
Recommended engine coolant
• When adding coolant, use only
distilled (deionized) water for your
vehicle and never mix hard water in
the coolant filled at the factory.
• An improper coolant mixture can result in severe malfunction or engine
damage.
• The engine in your vehicle has aluminum engine parts and must be
protected by an ethylene-glycol with
phosphate based coolant to prevent
corrosion and freezing.
• Do not use alcohol or methanol coolant or mix them with the specified
coolant.
• Do not use a solution that contains more than 60% antifreeze or less than
35% antifreeze, which would reduce
the effectiveness of the solution.
ENGINE COOLANT

Maintenance8-22
For mixing percentage, refer to the
following table:
Ambient
Temperature Mixture Percentage
(volume)
Antifreeze Water
5°F (-15°C) 35 65
-

13°F (-25°C) 40 60
-31°F (-35°C) 50 50
-49°F (-45°C) 60 40
Information
If in doubt about the mix ratio, a 50%
water and 50% antifreeze mix is the
easiest to mix together as it will be the
same quantity of each. It is suitable to use
for most temperature ranges of - 31°F and
higher.
WARNING
Make sure the coolant cap is properly
closed after refilling coolant. Otherwise
the engine could be overheated while
driving.
Engine room front viewEngine room front view
ODN8089052LODN8089052L
1. Check if the coolant cap label is straight In front.
2. Make sure that the tiny protrusions inside the coolant cap is securely
interlocked.
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WARNING
Never remove the engine
coolant reservoir tank/radiator
cap or the drain plug while the
engine and radiator are hot.
Hot coolant and steam may blow out
under pressure, causing serious injury.
Turn the engine off and wait until the
engine cools down. Use extreme care
when removing the engine coolant
reservoir tank/radiator cap. Wrap
a thick towel around it, and turn it
counterclockwise slowly to the first
stop. Step back while the pressure is
released from the cooling system. When
you are sure all the pressure has been
released, press down on the cap, using
a thick towel, and continue turning
counterclockwise to remove it.