2013 Subaru Impreza Spark Plug Replacement Guide

It is imperative that you ensure your spark plugs are in good condition. There’s a decent probability you will need to replace your old and worn out spark plugs several times while you own a a 2013 Subaru Impreza. Spark plugs are one of the most important components inside your engine as they begin the entire combustion process that starts and keeps your engine running for many thousands of miles. Like most engine components, spark plugs experience wear over time and eventually need replacement, but fortunately this is a repair you can do on your own. Chances are, if you’ve found yourself here, you have no idea how to do that, or perhaps you’d just like to know what kind of spark plugs you need to buy. The entire process of changing your spark plugs should take approximately 20-45 minutes. This article will go over everything you’ll need to know about your Subaru Impreza’s spark plugs, whether you need some baseline information or a full, step-by-step guide to performing a spark plug change.

Correct spark plugs on a 2013 Subaru Impreza

Recommended 2.5L H4 Turbocharged 2013 Subaru Impreza Spark Plugs

2.5L H4 Turbocharged: Autolite APP5325 Double Platinum Automotive Replacement Spark Plugs (4 Pack)
For the 2.5L H4 Turbocharged 2013 Subaru Impreza, you can use AUTOLITE APP5325 spark plugs. As this 2.5L H4 Turbocharged features 4 cylinders, ensure that you purchase at least 4 spark plugs in total.

Recommended 2.0L H4 2013 Subaru Impreza Spark Plugs

2.0L H4: Champion Copper Plus Small Engine 991 Spark Plug (Carton of 1) – REA8MCX
For the 2.0L H4 2013 Subaru Impreza, you can use CHAMPION 991 spark plugs. As this 2.0L H4 features 4 cylinders, ensure that you purchase at least 4 spark plugs in total.

These spark plugs are an exact fit for their respective engines and will match the required specifications. As this 2013 Subaru Impreza features a 4 cylinder engine, ensure you purchase 4 spark plugs. We always try to recommend the best possible spark plugs for the money, and these spark plugs are either a factory recomendation or an equivalent replacement available in today’s market at an affordable price.

How often should I change my spark plugs?

Generally, it is advised that you replace spark plugs once every 20,000 to 40,000 miles. Of course, please make sure to check your owner’s manual to determine the exact interval determined by Subaru for the 2013 Impreza. Of course, if you drive your vehicle more aggressively or own a Impreza with some modifications, you may want to consider changing your spark plugs closer to the 20,000 miles end of that spectrum.

However, there are also classic signs of a car that may potentially need a spark plug replacement early, such as:

  • Engine misfiring
  • Problems starting your engine
  • Rough idle

As a quick note, keep in mind that this list is absolutely not comprehensive, and these problems on their own do not definitively point to the spark plugs being the standalone culprit. However, the best way to prevent any issues with your vehicle is to take care of it with routine maintenance, and you are definitely doing so with the responsible decision to replace your Subaru Impreza’s spark plugs on a regular basis.

Changing spark plugs on a 2013 Subaru Impreza

This is a process you should be able to do on your own with some commonplace garage tools. Of course, consult your owner’s manual, as well as a factory service manual (FSM for short) or an equivalent Haynes or Chiltons manual. The video shown below does a good job of outlining the process.

Helpful Tools

A set of spark plug sockets is a must have. Certain spark plugs and engines make this job extremely difficult without one
As noted before, you should be able to complete a spark plug change with some regular tools you most likely already have. However, there are a few tools that are specific to this job that you may not have, and we also want to recommend some general tools that you should definitely have in your toolbox if you don’t already.

  • A torque wrench is a vital tool to have in your toolbox. You should check your factory service manual to determine the correct torque rating to use when installing the new spark plugs for your 2013 Subaru Impreza to be confident they are installed properly.
  • A spark plug gap tool. This allows you to check the gap of your spark plugs and modify it if necessary. Most plugs will come pregapped, but if this is not the case, you should absolutely have one of these.
  • A spark plug tester – this is definitely a niche tool, but it can save you a ton of time. Although we’ve discussed spark plug replacement being a good thing to replace regularly and not just when issues occur, you may also be replacing your spark plugs because of an issue. This tool can help you diagnose the exact problem.
  • A set of spark plug sockets – These come in extremely handy because many standard sockets are not deep enough for spark plugs. Additionally, some spark plug holes are a bit smaller, so it requires a thinner wall like the one featured in the product here to fit. The linked product also features a magnet to keep a good hold of the spark plug so you do not drop it into your engine bay!

Tips for changing spark plugs on your 2013 Subaru Impreza

It is a great idea to have some dielectric grease handy.
Be sure to reference the video above before you attempt to repair the spark plugs on your 2013 Subaru Impreza, as well as review your FSM (factory service manual). Additionally, we have some tips below here to help you as you do this repair.

  • Note that this is not official advice as many spark plug manufacturers advise against the use of anti-seize. However, I have heard from numerous old-school mechanics that they always apply a light coating of anti-seize to the threads of their spark plugs, especially on older vehicles.
  • You should replace spark plugs on a cold engine. Wait at least 30 minutes after your engine has been running before attempting to replace the spark plugs on your 2013 Subaru Impreza
  • It’s not a bad idea to use dielectric grease when installing new spark plugs. You can apply a small amount to the inside of the boot and the ceramic part of your spark plugs. It lessens the chance of voltage leak and helps avoid the misfortune of the boot fusing to the spark plug over time.
  • The most important thing is to avoid overtightening the plugs or worse, cracking them due to overtightenting. Use a torque wrench capable of lower, more precise torque ratings to be sure that you don’t make this mistake.
  • Before starting, disconnect the negative terminal of your battery. It’s a good idea to disconnect the battery anytime you work on the electrical system of your Subaru Impreza or any other vehicle.

Leave a Comment