21-EM-010H

GROUP
NUMBER
Engine
Technical Service Bulletin
SUBJECT:
DATE
21-EM-010H
MODEL(S)
September,
2021
Sonata (DN8a)
DN8A 1.6L TGDI MISFIRE
HIGH PRESSURE INJECTOR REPLACEMENT
Description: Certain 2020-2021 Sonata (DN8a) vehicles with 1.6T engines may exhibit a check
engine light in conjunction with a popping noise, abnormal smell from the engine compartment,
rough running, or reduced power due to a misfire.
Follow the inspection procedure outlined in this bulletin to inspect and identify any high pressure
injectors with burnt injector tip seals, and replace any affected injector and tip seals to repair the
condition.
Applicable Vehicles: 2020-2021MY Sonata (DN8a) equipped with 1.6L T-GDI engines (VINs
starting with 5NP).
Production Date Range: 10/22/2019 - 08/28/2020
Parts Information:
PART NUMBER
35310-2M417
PART NAME
INJECTOR COMPLETE
QTY
1
Circulate To: General Manager, Service Manager, Parts Manager, Warranty Manager, Service
Advisors, Technicians, Body Shop Manager, Fleet Repair
SUBJECT:
DN8A 1.6L TGDI MISFIRE HIGH PRESSURE INJECTOR REPLACEMENT
Warranty Information:
Model
Op Code
Operation
Op Time
INJECTOR ASSY-FUEL Refer to
(1EA~ALL) (T-GDI)
Sonata
WEBLTS
(DN8a)
for
current
DIAGNOSTIC TOOL
35310RQ0
labor time
OPERATION
Causal Part
Nature
Code
Cause
Code
35310-2M417
I3T
ZZ3
35310R5T
NOTE: Normal Warranty Applies.
Service Procedure:
1.
If the vehicle is diagnosed with having a
misfire and the ignition coil, spark plug, and
associated connections are identified to be
operating as designed, proceed to diagnose
as follows in step 2.
2.
Complete a leakdown test on the affected
cylinder exhibiting a misfire. If leakdown is
15% or greater, locate the source of
escaping air.
One possible source of a leak can be a GDI
injector underneath the intake manifold. If no
leak is found in this location, proceed further
for continued diagnosis.
NOTICE
Engine leak down test
instructions can be found at:
HMA Dealer Portal > Service
Information > Fix It Right >
Engine Mechanical System >
Engine Leak-Down Test.
NOTICE
One method to help determine
the source of an air leak is to
use the open end of a
stethoscope.
TSB #: 21-EM-010H
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SUBJECT:
SUBJECT: DN8A 1.6L TGDI MISFIRE HIGH PRESSURE INJECTOR REPLACEMENT
3.
Upon removal of the injector associated with
the engine’s misfire, the following conditions
may be shown on the right.
NOTICE
Conditions of burnt-out injector
tip seals can be soot deposits
around affected injector area
and cylinder boss.
4.
Upon removal of the GDI Injector, if injector
has the appearance as seen to the right,
replace the whole injector. Do not just
replace the tip seal of the injector in this
case.
5.
After replacing the injector, reinstall parts in
reverse order of removal.
6.
Clear any DTC’s present.
7.
Start the engine and check for any leaks at
idle, then briefly operate the vehicle to verify
repair is successful.
8.
The service procedure is complete.
TSB #: 21-EM-010H
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SUBJECT: