Owners of other Honda or Acura vehicles such as the Accord, Insight, Clarity, Fit, HR-V, CR-V, Pilot, Passport, Odyssey, Ridgeline, ILX, MDX, RDX, NSX, RLX and TLX may also find these DIY instructions to be helpful.

The OEM spark plugs in this 2016 Civic 2.0L I4 were the iridium tipped NGK DILKAR7H11GS (96964).

(The genuine Honda / Acura part number for the NGK plugs is Honda 12290-RDF-A01.)

A few other compatible replacement aftermarket spark plugs with their part numbers include the following: Autolite XP5682, Champion 9412, Denso 4712 and NGK DILKAR7G11GS (91578).

The tools and other items needed to complete this procedure include a 10mm socket with a 1/4" drive ratchet, a 14mm spark plug socket (or a 9/16" spark plug socket would also work), an extension bar, a 3/8" drive ratchet and a tube of dielectric grease.

The first steps are to open the hood and then locate the four black metal bolts on the plastic engine cover.

There is one bolt near each of the four corners of the plastic cover.

Set the cover aside in a safe place along with the four black metal bolts.

If you have access to compressed air or a wet/dry vacuum, clean off the top of the engine to help reduce the risk of having sand, dirt or other debris fall down into the spark plug well.

Push in the release tab on on the electrical connector before sliding it straight off the base of the ignition coil housing.

I recommend only checking or changing one spark plug at a time to help further reduce the risk of having a foreign object fall down into the cylinder.

I found it easiest to attach a short extension bar to my socket and ratchet to get some clearance above the ignition coil.

Once the bolt is loose, spin it out the rest of the way by hand to help prevent from having fall down into the engine bay and possibly become lost.

Set the bolt aside in a safe place.

Lift the ignition coil straight out of the spark plug well and set it aside in a safe place.

The OEM ignition coil part number was Hitachi CM11-121A 17105 which is Honda part number 30520-5R0-013.

If your Civic has been displaying a CEL / SES (check engine light / service engine soon) warning on the gauge cluster, you can check the issue with an OBDII Scanner (also known as an OBD 2 scan tool).

If the DTC (diagnostic trouble code) is related to the ignition coils such as P0350, P0351, P0352, P0353 or P0354, you may need to replace a failing or faulty ignition coil module. (You could also try checking and cleaning the electrical connector.)

A few compatible replacement aftermarket ignition coils with their part numbers include the following: Delphi GN10734, Standard Motor Products UF749 and Spectra Premium C-970.

(A 9/16" spark plug socket would also work since 9/16" is just slightly larger at 14.2875mm.)

I like to use some painter's tape to secure the socket to the extension bar to help prevent it from popping off and being stuck down in the spark plug well.

Lower the socket into the well and push it on to the top of the old spark plug.

Loosen the old spark plug by turning it in the counterclockwise direction.

If you have trouble loosening the old spark plug, try spraying a small amount of penetrating oil such as Liquid Wrench, PB Blaster or even WD-40 down into the well.

Allow the penetrating oil to work down into the threads for at least 5 to 10 minutes.

Try to avoid using excessive force, the old spark plug should break free relatively easily.

If you live in a very cold climate or close to corrosive salt water, you could try warming up the engine or allowing the penetrating oil to seep in for an hour or two.

Do not use an excessive amount of penetrating oil. Just a short 1/2 second spray (a few drops) is enough for each spark plug well.

Spin out the old spark plug the rest of the way by hand.

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

Inspect both ends of the old spark plug.

If the old plug is covered in oil, soot or black powder, the engine might be burning oil and should be checked by a professional mechanic.

On the other hand, if the old plug is covered in white powder and appears discolored, the engine may have been subjected to over heating and you should have the cooling system checked.

The OEM (original equipment manufacturer) spark plugs in this 2016 Civic were the NGK DILKAR7H11GS Laser Iridium which should be pre-gapped from the factory to 0.044".

If you have a spark plug gap gauge, double check the gap on the new spark plugs.

Push the new spark plug into the socket.

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

Carefully lower the new spark plug down into the well.

Try to avoid hitting the electrode tip against the top of the engine or the walls of the spark plug well.

Spin in the new spark plug by hand by just using the extension bar. Do not attach the ratchet at this point.

Continue spinning the spark plug in the clockwise direction until it is finger tight with just the extension bar.

Then attach the 3/8" drive ratchet and tighten the new plug.

If you are installing a new spark plug, tighten it to just a fraction of a turn past the point when you feel the new crush washer collapse.

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

Try to avoid over tightening the spark plug. The plug only needs to be "snug".

I've never used a torque wrench to tighten spark plugs since you can easily over tighten them. But if you insist on using a torque wrench, the service manual specification is 13 lb-ft (or 18 N-m).

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

Apply a small amount of dielectric grease to the opening in the dust boot.

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

Lower the ignition coil into the well and push it down on to the top of the new spark plug.

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

Spin in the bolt a few turns by hand in the clockwise direction to help prevent it from becoming cross threaded.

Tighten the bolt 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 assembly.

Push the electrical connector straight on to the base of the ignition coil.

You should feel or hear the power plug "click" securely into place.

Lower the plastic cover over the top of the engine.

(Please note, the 1.5L turbo engine does not have a plastic cover like the 2.0L I4 shown on this page.)

Avoid over tightening the bolts to prevent from cracking the plastic cover.

Start the engine and listen closely for any strange sounds or other noises that might indicate a problem such as a loose spark plug, faulty ignition coil or a disconnected electrical connector.

Be sure to write down the plug change in your vehicle's service records.

Please check out all of my 2016-2019 Honda Civic DIY Repair & Maintenance Guides.