Owners of other Hyundai or Kia vehicles such as the Elantra, Sonata, Azera, Santa Fe, Tucson, Accent, Ioniq, Genesis, Tiburon, ix20, i20, i30, i40, Veracruz, Optima, Cadenza, K900, Soul, Niro, Sportage, Sorento, Sedona, Rio, Forte and Spectra may also find these DIY instructions to be helpful.

The OEM spark plugs in this 2017 Veloster were part number NGK Iridium SILZKR6B10E (also known as SILZKR6B-10E).

A few other compatible replacement spark plugs with their part numbers are as follows: Champion RER8ZWYCB4 (9407), Autolite XP6203, Denso ZXU20HCR8, Pulstar GG1H10 and genuine OEM Hyundai 18846-10060.

The tools needed to complete this procedure include a small flathead screwdriver, a 10mm socket, a 1/4" drive ratchet, a 5/8" spark plug socket, an extension bar and a 3/8" drive ratchet.

The plastic cover is held in place by four rubber friction fasteners attached to four metal pegs on the top of the engine.

Set the engine cover aside in a safe place.

If you have access to compressed air or a wet/dry shop vacuum, thoroughly clean off the top of the engine to help reduce the risk of having debris fall down in to the spark plug cylinder.

I recommend only checking or changing one spark plug at a time to help further eliminate the risk of having dirt fall down in the engine's cylinder block.

Use a 10mm socket and a 1/4" drive ratcheting wrench to loosen the ignition coil bolt in the counterclockwise direction.

Rotate the ignition coil back and forth a few times to make sure that the rubber dust boot at the end of it is not stuck or "frozen" to the top of the old spark plug.

Lift out the ignition coil and set it aside in a safe place.

I like to secure the spark plug socket to the extension bar with some painters tape to reduce the risk of having it pop off and fall down to the bottom of the spark plug well.

Lower the socket over the top of the old spark plug.

Carefully loosen the old spark plug by turning it in the counterclockwise direction.

Try to avoid using excessive force to loosen the old spark plug to prevent from cracking the ceramic portion of the plug.

If you have trouble loosening the old spark plug, spray a small amount of penetrating oil such as PB Blaster, Liquid Wrench or Kano Kroil and wait at least 15 to 30 minutes before attempting to loosen it again. If you don't have any penetrating oil, try spraying some WD-40 or warm up the engine for a few minutes to help expand the metal engine block.

Once the old spark plug is loose, detach the ratchet from the extension bar and spin it out the rest of the way by hand.

Lift the old spark plug out of the well and detach it from the socket.

Inspect both ends of the old spark plug.

If the electrode end of the old spark plug appears to be ashy white, the plugs might have been exposed to high temperatures such as overheating or they might be the incorrect heat range for your driving conditions or environment.

If the electrode tip of the old spark plug is grey or covered in dark black soot, the engine might be burning oil and should be inspected by a professional mechanic.

The OEM spark plugs in this 2017 Hyundai Veloster equipped with the Gamma GDI 1.6L I4 engine are the NGK Iridium part number SILZKR6B10E (also referred to as # SILZKR6B-10E).

(An optional step is to apply some anti-seize grease to the threads on the spark plug. Most spark plug manufacturers recommend that you should not use anti-seize lubricant grease since it can lead to over tightening. Although some mechanics believe that using anti-seize grease on the new spark plugs will help prevent them from becoming stuck or "frozen" in the cylinder head if they are not removed again for another 100,000 miles.)

If you have a spark plug gap gauge, verify that the new spark plugs are gapped to the manufacturer's specification listed on the box.

Push the new spark plug in to the 5/8" socket.

Your spark plug socket should have a strong magnet or a rubber insert to securely hold the new spark plug in place.

Lower the spark plug down in to the well and spin it in by hand in the clockwise direction until it makes contact with the cylinder block.

If you are re-installing the old spark plug, tighten it to just a small fraction of a turn past hand tight.

If you are installing a new spark plug, carefully tighten the spark plug until you feel the new crush washer collapse, which should be about 1/8 to 1/4 of a turn past when it first makes contact with the engine block.

Try to avoid over tightening the spark plug to prevent from cracking the ceramic part of the plug or stripping the threads.

Double check that the new spark plug is tight before moving on to the next step.

The dielectric grease will help keep out any moisture or debris and ensure a reliable electrical connection.

Lower the ignition coil down in to the spark plug well.

Rotate the ignition coil back and forth a few times to help spread around the dielectric grease.

Tighten the ignition coil bolt by turning it in the clockwise direction with the 10mm socket and a 1/4" drive ratchet until it is snug.

Try to avoid over tightening the bolt to prevent from cracking the plastic ignition coil housing.

Push the power plug on to the ignition coil until it clicks securely in to place.

Lower the plastic cover over the engine and push it down in to place to secure the four rubber friction fasteners.

Start the engine and listen for any strange sounds that might indicate a loose spark plug or a disconnected electrical connector.

Be sure to record the spark plug change in your car's service records.

For more, check out all of my 2012-2017 Hyundai Veloster DIY Repair & Maintenance Guides.