Inspection And Cleaning

Disconnect the spark plug cable from the spark plug.
NOTE: Pull on the spark plug cable boot when removing the spark plug cable, not the cable, as it may be damaged.
Using spark plug wrench, remove all of the spark plugs from the cylinder head.
CAUTION: Take care not to allow contaminants to enter through the spark plug holes because severe engine damage could occur.
Check spark plugs for the following:
1. Broken insulator
2. Worn electrode
3. Carbon deposits
4. Damaged or broken gasket
5. Condition of the porcelain insulator at the tip of the spark plug.
Fig 1: Identifying Spark Plug Components
Courtesy of KIA MOTORS AMERICA, INC.
Check the spark plug gap using a wire gap gauge, and adjust if necessary.
Standard value :

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

Fig 2: Checking Spark Plug Gap
Courtesy of KIA MOTORS AMERICA, INC.
Install the spark plug and tighten to the specified torque.
CAUTION: If the spark plug is over-tightened, damage to the threaded portion of the cylinder head may result.

Tightening torque

Spark plug : 20-30 Nm (204-306 kg. cm, 15-21 lb. ft)