There’s a decent chance you will need to replace your old and worn out spark plugs several times over the course of owning a 2003 Mazda Protege5. Spark plugs are one of the most vital parts inside your engine as they start the entire combustion process that starts and keeps your engine running for many thousands of miles. Similar to most engine parts and components, spark plugs experience wear over time and eventually need to be replaced, 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 about 20-45 minutes. This article will go over everything you should need to know about your Mazda Protege5’s spark plugs, whether you need some general information or a full, step-by-step guide to performing a spark plug change.
Correct spark plugs on a 2003 Mazda Protege5
NGK 5464[/caption]For any 2003 Mazda Protege5, you can use NGK 5464 spark plugs. These will be an exact fit and will match the required specifications of your engine. As this 2003 Mazda Protege5 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 now at an affordable price.
How often should I change my spark plugs?
As a general recommendation, 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 specific interval determined by Mazda for the 2003 Protege5. Of course, if you drive your vehicle more aggressively or own a Protege5 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 need a spark plug replacement prematurely, such as:
- Problems starting your engine
- Rough idle
- Engine misfiring
Note that this list is of course 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 regular maintenance, and you are definitely doing so with the responsible decision to replace your Mazda Protege5’s spark plugs on a regular basis.
Changing spark plugs on a 2003 Mazda Protege5
This is a process you can do on your own with some ordinary 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.
As noted before, you should be able to complete a spark plug change with some ordinary 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 commonplace tools that you should absolutely have in your toolbox if you don’t already.
- 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 something going wrong. This tool can help you diagnose the exact problem.
- A torque wrench is a very important tool to have in your collection. You will want to check your FSM (factory service manual) or owner’s manual to determine the correct torque rating to use when inserting the new spark plugs for your 2003 Mazda Protege5 to be sure they are installed properly.
- A set of spark plug sockets – These come in very handy because many standard sockets are not deep enough for spark plugs. Also, 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!
- A spark plug gap tool. This allows you to check the gap of your spark plugs and change it if necessary. Most plugs will come pregapped, but if this is not the case, you should definitely have one of these.
- I also highly recommend you have a feeler gauge as it makes it a bit easier to check the exact gap, and it is helpful for a decent number of other jobs.
Tips for changing spark plugs on your 2003 Mazda Protege5
Please make sure you review the video above before you attempt to repair the spark plugs on your 2003 Mazda Protege5, as well as review your factory service manual. Be sure to check the tips shown here to help you as you complete this repair.
- 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.
- Before starting, disconnect the negative terminal of your battery. It is wise to disconnect the battery anytime you work on the electrical system of your Mazda Protege5 or any other vehicle.
- One of the most important things to remember 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.
- 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 prevents voltage leak and helps avoid the misfortune of the boot fusing to the spark plug over time.
- You should replace spark plugs on a cold engine. Ensure you wait at least 30 minutes after any kind of operation before attempting to replace the spark plugs on your 2003 Mazda Protege5