The 2005 Hyundai Sonata is a Korean built, mid-sized sedan with European styling. The engine compartment is located at the front of the vehicle, under the hood. Engine access is needed to complete this procedure. You can perform the spark plug replacement procedure with common tools and little to no experience. Refer to the 2005 Hyundai Sonata service manual for the factory recommended parts and parts numbers needed.
Remove the engine cover located on top of the engine.
Wipe around the base of each spark plug with a clean cloth to remove any debris.
Remove the ignition cover by twisting counter clockwise with a flat-head screwdriver. The ignition cover is located on the top of each spark plug ignition coil.
Press in the ignition connector key located on the right side of the wiring harness. Pull the connector away from the ignition coil.
Locate the mounting bolt on top of the ignition coil. Using a socket and wrench, turn the bolt counter-clockwise until it is removed. Pull straight up on the ignition coil to reveal the spark plug.
Turn the spark plug counter-clockwise, being careful not to damage the ceramic insulator on the spark plug. You can perform this task by using a socket wrench specifically designed for spark plug installation and removal.
Place the spark plug installation socket over the new spark plug. Insert into the top of the engine cylinder. Turn clockwise with the socket wrench until spark plug is tightened.
Replace the ignition coil and bolt.
Press the wiring harness back on.
Replace the ignition cover.
Replace the engine cover.
