WARNING:

When working on the high voltage system, the work should be performed by technicians who have completed the relevant training. A lack of understanding of the high voltage system can lead to serious accidents due to electric shock or short circuit.
When working on the high voltage system or related components, be sure to observe and be aware of the "HIGH VOLTAGE SYSTEM GENERAL SAFETY INFORMATION AND CAUTION ". If not, it may cause serious accidents due to electric shock or short circuit.
When working on high voltage system, make sure to check the PERSONAL PROTECTIVE EQUIPMENT (PPE) and HIGH VOLTAGE SHUT-OFF PROCEDURES .

Check the DTC code by using the KDS (Refer to "DTC INDEX (PHEV) ").

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Check the connection condition of the ignition coil connectors (A).

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Check the installation condition of the ignition coils (A).
Tightening torque:

9.8 - 11.8 N.m (1.0 - 1.2 kgf.m, 7.2 - 8.7 lb.ft)

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Remove the spark plug.
(Refer to Spark Plug - "REMOVAL AND INSTALLATION ")

Visual inspection of the spark plugs.

Spark plug electrode gap: 1.0 - 1.1 mm (0.039 - 0.043 in.)

Symptom	Suspected Cause	Correction
Courtesy of KIA MOTORS AMERICA, INC. Melting Electrode	Abnormal Combustion, Overheat	Replace the Spark Plug
Courtesy of KIA MOTORS AMERICA, INC. Carbon and Foreign Matter	Abnormal Combustion, Overheat
Courtesy of KIA MOTORS AMERICA, INC. Ring Crack	Abnormal Combustion, External Shock
Courtesy of KIA MOTORS AMERICA, INC. Vertical Crack	External Shock
Courtesy of KIA MOTORS AMERICA, INC. Overheat	Abnormal Combustion

Symptom	Suspected Cause	Correction
Courtesy of KIA MOTORS AMERICA, INC. Poor Gap	Physical Damage	Replace the Spark Plug
Courtesy of KIA MOTORS AMERICA, INC. Flash Over	Excessive Electrode Wear	Replace the Spark Plug, Ignition Coil
Courtesy of KIA MOTORS AMERICA, INC. Corrosion/Rust	Remaining Oil Mist	Reassemble the Spark Plug