Save Money On Car Maintenance: How To Change Spark Plugs On A Honda Civic 2018

Quick summary

An extension may be needed to reach the spark plugs in the back of the engine.
The spark plugs are located on the top of the engine, usually under a plastic cover.
If everything seems fine, let the engine run for a few minutes to allow the new spark plugs to warm up.

Are you looking for a DIY project to improve your Honda Civic’s performance and fuel efficiency? Changing the spark plugs is a relatively simple task that can make a noticeable difference. This guide will walk you through the process of changing spark plugs on a 2018 Honda Civic, providing step-by-step instructions and helpful tips.

Why Change Spark Plugs?

Spark plugs are essential components in your car’s engine. They ignite the air-fuel mixture in the combustion chamber, which powers the engine. Over time, spark plugs wear down and become less efficient, leading to:

Reduced engine performance: A worn-out spark plug may misfire, causing a loss of power and acceleration.
Poor fuel economy: Inefficient combustion leads to wasted fuel, resulting in lower gas mileage.
Rough idling: Misfires can also cause the engine to idle roughly or stall.
Increased emissions: Worn spark plugs can contribute to higher emissions, harming the environment.

The recommended replacement interval for spark plugs varies depending on the type and model of your car. For a 2018 Honda Civic, it’s typically around 100,000 miles. However, it’s always a good idea to check your owner’s manual for the specific recommendations for your vehicle.

Gather Your Supplies

Before you begin, make sure you have all the necessary tools and materials:

New spark plugs: Ensure you purchase the correct type and model for your 2018 Honda Civic. Consult your owner’s manual or a reliable online parts catalog to find the right spark plugs.
Spark plug socket: This specialized tool is designed to remove and install spark plugs. It’s usually available in a 5/8″ or 16mm size.
Torque wrench: This tool is crucial for tightening the spark plugs to the correct specifications. Over-tightening can damage the spark plug threads, while under-tightening can lead to leaks.
Ratchet: This tool is used to turn the spark plug socket.
Extension: An extension may be needed to reach the spark plugs in the back of the engine.
Gloves: Protect your hands from grease and dirt.
Safety glasses: Protect your eyes from flying debris.
Shop towels: Clean up any spills or messes.

Step-by-Step Guide to Changing Spark Plugs

1. Prepare the Vehicle:

Park your Honda Civic on a level surface and engage the parking brake.
Open the hood and disconnect the negative terminal of the battery to prevent electrical shocks.

2. Locate the Spark Plugs:

The spark plugs are located on the top of the engine, usually under a plastic cover.
For a 2018 Honda Civic, you’ll find four spark plugs arranged in a row.

3. Remove the Spark Plug Cover:

If your Civic has a spark plug cover, carefully remove it.
Some covers are secured with clips, while others may have screws.

4. Remove the Old Spark Plugs:

Using the spark plug socket and ratchet, loosen the spark plugs by turning them counter-clockwise.
Be careful not to drop the spark plugs into the engine cylinder.
Once loosened, remove the spark plugs by hand.

5. Inspect the Old Spark Plugs:

Examine the old spark plugs for signs of wear and tear.
Look for excessive wear on the electrodes, cracks in the ceramic insulator, or excessive carbon buildup.
If you notice any of these issues, it’s a good indication that the spark plugs need to be replaced.

6. Install the New Spark Plugs:

Thread the new spark plugs into the cylinder head by hand, ensuring they are seated correctly.
Do not force the spark plugs, as this can damage the threads.
Once the spark plugs are hand-tightened, use the torque wrench to tighten them to the specified torque. The torque specifications for a 2018 Honda Civic are typically around 13-15 ft-lbs.

7. Reinstall the Spark Plug Cover:

Replace the spark plug cover and secure it with the clips or screws.

8. Reconnect the Battery:

Connect the negative terminal of the battery.

9. Start the Engine:

Start the engine and listen for any unusual noises or misfires.
If everything seems fine, let the engine run for a few minutes to allow the new spark plugs to warm up.

10. Test Drive:

Take your Honda Civic for a test drive to ensure the new spark plugs are working properly.
You should notice a smooth idle, improved acceleration, and better fuel efficiency.

Tips for Success

Use a spark plug gap tool: Ensure the gap between the electrodes on your new spark plugs is set correctly. You can use a spark plug gap tool to adjust the gap if necessary.
Clean the spark plug wells: Before installing the new spark plugs, clean the spark plug wells with a shop towel to remove any dirt or debris.
Use a lubricant: Applying a small amount of anti-seize lubricant to the threads of the new spark plugs can help prevent them from seizing in the cylinder head.
Don’t over-tighten: Over-tightening the spark plugs can damage the threads and lead to leaks. Use a torque wrench and follow the specified torque specifications.
Be patient: Changing spark plugs can be a time-consuming process, so be patient and take your time.

Beyond the Basics: When to Seek Professional Help

While changing spark plugs is a relatively straightforward DIY project, there are times when it’s best to seek professional help. If you encounter any of the following issues, it’s recommended to have a mechanic inspect your Civic:

Difficult access: The spark plugs on some vehicles may be difficult to access due to their location or tight spaces.
Damaged or seized spark plugs: If the spark plugs are damaged or seized, it may be difficult or impossible to remove them without specialized tools or expertise.
Engine problems: If you experience engine problems such as misfires, rough idling, or loss of power, it’s important to have your car inspected by a mechanic to rule out other potential issues.

Spark Plug Success: A Final Thought

Changing spark plugs on your 2018 Honda Civic is a worthwhile DIY project that can improve your car’s performance and fuel efficiency. By following these steps and taking the necessary precautions, you can successfully complete this task and enjoy the benefits of a smooth-running engine.

Save Money on Car Maintenance: How to Change Spark Plugs on a Honda Civic 2018