The 6 Biggest Mistakes Men Make When Replacing Their Own Spark Plugs
Your spark plugs have a profound impact on the way your car runs. In fact, they can cause your vehicle not to start if they’ve gone bad. That said, they’re fairly easy to replace on your own. If you’re choosing to DIY this car repair, there are several mistakes you’ll want to avoid when replacing your own spark plugs. Here they are.
1. Choosing the Wrong Spark Plugs
As a former mechanic, I saw plenty of people coming in not knowing what was wrong with their vehicle. After some investigating, we found out that they’d recently replaced their spark plugs on their own but chose the wrong kind. Choosing the wrong plugs can mess with your car’s performance. Many people overlook the recommendations being made by the manufacturer, opting for something cheaper or “better.” However, installing the wrong type can actually lead to misfires, rough idling, or long-term engine damage. So, it’s key to check your owner’s manual before you replace them.
2. Skipping the Gap Check
Factory-set gaps might seem convenient, but assuming they’re correct is a rookie mistake. Even pre-gapped spark plugs can shift during shipping, leading to inefficient combustion or misfires. Using a gap gauge to check and adjust the gap according to your vehicle’s specs is essential. Too wide a gap can cause weak sparks, while a gap that’s too narrow can lead to poor fuel combustion.
3. Ignoring Anti-Seize and Dielectric Grease
Many men skip using anti-seize on spark plug threads and dielectric grease on boot terminals, thinking it’s unnecessary. However, anti-seize prevents plugs from welding to the cylinder head, making future replacements much easier. Dielectric grease, on the other hand, protects connections from moisture and corrosion, ensuring a strong electrical link. Without these, you might struggle to remove plugs later or face ignition problems.
4. Over-Tightening or Under-Tightening Plugs
Torque specs are super important for many things when it comes to your car, including your spark plugs. Over-tightening the spark plugs can strip the threads or even crack the ceramic insulator. On the other hand, over-tightening them could potentially cause compression loss or the plugs could blow out. So, it’s important to use a torque wrench if you want to avoid expensive repairs. And again, consult the owner’s manual for torque specs.
5. Forgetting to Clean the Area Around the Plugs
It’s easy to pull out old spark plugs without cleaning the surrounding area first, but that’s a fast track to engine trouble. Dirt and debris can fall into the combustion chamber, leading to scoring or even a seized engine. Use compressed air to blow away contaminants before removing the plugs. Even a small amount of grit can cause significant problems over time.
6. Replacing Only Some of the Plugs
Don’t try to save money or time by only replacing select spark plugs. Even though some of them might look worse than others, they all wear out at about the same rate. Only replacing a few at a time can lead to imbalance in engine performance. It can also cause misfires, rough idling, and poor fuel efficiency. Just change them all at once to avoid the headache.
Avoid These Mistakes for a Smoother Ride
Replacing your own spark plugs isn’t very complicated, but it’s easy to make small mistakes that could lead to costly repairs down the road. If you are considering replacing your own spark plugs, make sure you’re aware of these common pitfalls before you begin. When in doubt, bring your car to the shop. They won’t charge you much to replace your spark plugs and it’ll ensure everything is done right.
Read More
Your Transmission Is Screaming for Help—Do These 5 Things Before It’s Too Late
7 Most Forgettable Cars in History
Drew Blankenship is a former Porsche technician who writes and develops content full-time. He lives in North Carolina, where he enjoys spending time with his wife and two children. While Drew no longer gets his hands dirty modifying Porsches, he still loves motorsport and avidly watches Formula 1.