2018 Hyundai Sonata Plug-in Hybrid fuel filter

7
Maintenance
7-9
Normal Maintenance Schedule
The following maintenance services must be performed to ensure good emission control and performance.
Keep receipts for all vehicle emission services to protect your warranty. Where both mileage and time are shown, the
frequency of service is determined by whichever occurs first.
Number of months or driving distance, whichever comes first
Months1224364860728496108120132144156168180
Miles7.51522.53037.54552.56067.575839098105113
Km1224364860728496108120132144156168180
HSG belts *1Inspect every 7,500 miles or 12 months,
and replace every 67,500 miles or 48 months
Engine oil and engine oil filterRRRRRRRRRRRRRRR
Fuel additives *2Add fuel additives every 7,500 miles or 12months
Air cleaner filterIIIRIIIRIIIRIII
Spark plugsReplace every 97,500 miles
Rotate tiresRotate tires every 7,500 miles
Climate control air filterReplace every 15,000 miles or 12 months
Vacuum hoseIIIIIIIIIIIIIII
Engine coolant / Inverter coolantAt first, replace at 120,000 miles or 10 years :
after that, replace every 30,000 miles or 24 months
MAINTENANCE INTERVALS
MAINTENANCE
ITEM
I : Inspect and if necessary, adjust, correct, clean or replace.
R : Replace or change.
*
1: The drive belt should be replaced when cracks occur or tension is reduced excessively.
*2: If TOP TIER Detergent Gasoline is not available, one bottle of additive is recommended. Additives are available from your authorized HYUNDAI dealer along with information on how to use them. Do not mix other additives.

7
Maintenance
7-11
Normal Maintenance Schedule (CONT.)
Number of months or driving distance, whichever comes first
Months1224364860728496108120132144156168180
Miles7.51522.53037.54552.56067.575839098105113
Km1224364860728496108120132144156168180
Fuel tank air filter *3IIIIIII
Fuel filter *3IIIIIII
Fuel lines, hoses and connectionsIIIIIII
Parking brakeIIIIIII
Brake fluidIIIIIII
MAINTENANCEINTERVALS
MAINTENANCE
ITEM
I : Inspect and if necessary, adjust, correct, clean or replace.
R : Replace or change.
*
3: Fuel filter & Fuel tank air filter are considered to be maintenance free\
but periodic inspection is recommended for this mainte- nance schedule depends on fuel quality. If there are some important safety matters like fuel flow restriction, surging, loss of
power, hard starting problem, etc. replace the fuel filter immediately regardless of maintenance schedule a\
nd consult an
authorized HYUNDAI dealer for details.

7-14
Maintenance
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Engine oil and filter
The engine oil and filter should be
changed at the intervals specified in
the maintenance schedule. If the car
is being driven in severe conditions,
more frequent oil and filter changes
are required.
HSG (Hybrid starter & genera-
tor) belt
The HSG belt should be changed at
the intervals specified in the mainte-
nance schedule.
Fuel filter
A clogged filter can limit the speed at
which the vehicle may be driven,
damage the emission system and
cause multiple issues such as hard
starting. If an excessive amount of
foreign matter accumulates in the
fuel tank, the filter may require
replacement more frequently. After
installing a new filter, run the engine
for several minutes, and check for
leaks at the connections. Fuel filters
should be installed by an authorized
HYUNDAI dealer.
Fuel lines, fuel hoses and con-
nections
Check the fuel lines, fuel hoses and
connections for leakage and dam-
age. Have an authorized HYUNDAI
dealer replace any damaged or leak-
ing parts immediately.
Vapor hose and fuel filler cap
The vapor hose and fuel filler cap
should be inspected at those inter-
vals 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.

7-84
Maintenance
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The emission control system of your
vehicle is covered by a written limited
warranty. Please see the warranty
information contained in the Owner’s
Handbook & Warranty Information
booklet in your vehicle.
Your vehicle is equipped with an
emission control system to meet all
applicable emission regulations.
There are three emission control
systems, as follows.
(1) Crankcase emission control sys-
tem
(2) Evaporative emission control sys- tem
(3) Exhaust emission control system
In order to assure the proper function
of the emission control systems, it is
recommended that you have your
vehicle inspected and maintained by
an authorized HYUNDAI dealer in
accordance with the maintenance
schedule in this manual.1. Crankcase emission control system
The positive crankcase ventilation
system is employed to prevent air
pollution caused by blow-by gases
being emitted from the crankcase.
This system supplies fresh filtered air
to the crankcase through the air
intake hose. Inside the crankcase,
the fresh air mixes with blow-by
gases, which then pass through the
PCV valve into the induction system.
2. Evaporative emission controlsystem including onboard
refueling vapor recovery
(ORVR)
The Evaporative Emission Control
System is designed to prevent fuel
vapors from escaping into the atmos-
phere. The ORVR system is
designed to allow the vapors from
the fuel tank to be loaded into a can-
ister while refueling at the gas sta-
tion, preventing the escape of fuel
vapors into the atmosphere.
For the Inspection and
Maintenance Test (With
Electronic Stability Control
(ESC) system)
To prevent the vehicle from
ESC activation during
dynamometer testing, turn the
Electronic Stability Control
(ESC) system off by pressing
the ESC switch (ESC OFF
light illuminated).
After dynamometer testing is
completed, turn the ESC sys-
tem back on by pressing the
ESC switch again.
CAUTION

I-4
Driver assist system ......................................................3-119Rear parking assist system .......................................3-120
Rear parking assist system precautions....................3-123
Rear view camera .....................................................3-119
Driver attention alert system (DAA) ..............................5-63 Resetting the system ...................................................5-65
System malfunction ....................................................5-65
System setting and activation .....................................5-63
System standby...........................................................5-65
Driver position memory system .....................................3-14 Easy Access Function .................................................3-15
Storing Positions into Memory ..................................3-14
Driving the Hybrid/Plug-in Hybrid Vehicle ....................H22 Changing plug-in hybrid mode ...................................H26
Energy flow.................................................................H38
Hybrid system gauge ..................................................H24
Special features ...........................................................H23
Starting the vehicle .....................................................H22
Warning and indicator lights.......................................H27
Warning messages.......................................................H28 Emission control system .................................................7-84
Crankcase emission control system ...........................7-84
Evaporative emission control system including onboard refueling vapor recovery (ORVR) ............7-84
Exhaust emission control system ...............................7-85
Engine ........................................................................\
.......8-2
Engine compartment..................................................1-6, 7-3
Engine coolant/inverter coolant ......................................7-19 Changing engine coolant ............................................7-22
Checking the engine/inverter coolant level................7-19
Engine number ..................................................................8-9
Engine oil ........................................................................\
7-17 Checking the engine oil and filter ..............................7-18
Checking the engine oil level .....................................7-17
Engine Start/Stop button ...................................................5-5 Engine Stop/Start button positions ...............................5-7
Illuminated Engine Start/Stop button ...........................5-6
Starting the hybrid system............................................5-9
Explanation of scheduled maintenance items.................7-14
Exterior features..............................................................3-46 Fuel Filler Door (Hybrid) ...........................................3-53
Fuel Filler Door (Plug-in hybrid) ...............................3-56
Hood ........................................................................\
...3-46
Smart Trunk ................................................................3-50
Trunk ........................................................................\
..3-47
Index
E