Spark plugs are one of the most critical components inside your engine that need to be maintained. There’s a good probability you will need to replace your worn out spark plugs several times over the course of owning a 2008 Mazda CX-9. Spark plugs are one of the most critical components inside your engine as they trigger the entire combustion process that starts and keeps your engine running for many thousands of miles. Similar to most engine components, spark plugs experience wear over time and eventually need to be swapped out for new replacements, 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 complete process of changing your spark plugs should take approximately 20-45 minutes. This article will go over everything you should need to know about your Mazda CX-9’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 2008 Mazda CX-9
DENSO 5339[/caption]For any 2008 Mazda CX-9, you can use DENSO 5339 spark plugs. These will be an exact fit and will match the required specifications of your engine. As this 2008 Mazda CX-9 features a 6 cylinder engine, ensure you purchase 6 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 a reasonable 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 specific interval determined by Mazda for the 2008 CX-9. Of course, if you drive your vehicle more aggressively or own a CX-9 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 needs a spark plug replacement earlier than the recommended schedule, such as:
- Problems starting your engine
- Rough idle
- Engine misfiring
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 organized maintenance, and you are definitely doing so with the responsible decision to replace your Mazda CX-9’s spark plugs on a regular basis.
Changing spark plugs on a 2008 Mazda CX-9
This is a process you can do on your own with some standard garage tools. Of course, consult your owner’s manual, as well as a factory service manual 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 accomplish 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 spark plug gap tool. This allows you to check the gap of your spark plugs and increase or decrease it if necessary. Most plugs will come pregapped, but if not, you should definitely have one of these.
- I also highly recommend you have a feeler gauge as it makes it a bit more straightforward to check the exact gap, and it comes in handy for countless other jobs.
- A torque wrench is a essential tool to have in your garage. You should check your factory service manual to determine the correct torque rating to use when inserting the new spark plugs for your 2008 Mazda CX-9 to be certain they are installed properly.
- A set of spark plug sockets – These come in extremely 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 tester – this is definitely a niche tool, but it can save you lots 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.
Tips for changing spark plugs on your 2008 Mazda CX-9
Please make sure you watch the video above before you attempt to repair the spark plugs on your 2008 Mazda CX-9, as well as review your FSM (factory service manual) or owner’s manual. Be sure to check the tips shown here to help you as you perform this repair.
- 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 isn’t 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.
- Before beginning, 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 Mazda CX-9 or any other vehicle.
- 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 small amount of anti-seize to the threads of their spark plugs, especially on older vehicles.
- Your engine should be cold before you replace your spark plugs. Wait at least 30 minutes after your engine has been running before attempting to replace the spark plugs on your 2008 Mazda CX-9