Is your car starting rough, idling strangely, or losing power when you hit the gas? These small problems can point to one simple fix: spark plugs that need to be replaced—one of the most common electrical issues with cars!
In this blog, we’ll discuss the top signs of bad plugs and how often they should be replaced. You’ll learn what to look for, how spark plugs affect your engine, and why timely replacements matter more than most people think. Let’s get started.
How to Tell if a Spark Plug Is Bad
So, how many spark plugs does a car have? Most four-cylinder engines have four, but some vehicles have six or eight, depending on the engine design. And how often should spark plugs be changed? It depends on your car, but many need new plugs every 30,000 to 100,000 miles. Still, you don’t have to guess—your car will usually show signs that you need new spark plugs.
Here are five bad spark plug symptoms you should know:
1) Engine Misfires
A misfire is one of the clearest signs you need new spark plugs. You might feel it as a sudden jerk or stumble during acceleration. Worn plugs cause inconsistent firing and break up the engine’s rhythm.
2) Poor Fuel Economy
If your mileage drops for no clear reason, worn spark plugs could be to blame. When plugs don’t fire properly, your engine burns more fuel to get the same work done.
3) Trouble Starting
Struggling to get your engine going? One bad spark plug can delay ignition. If it happens alongside other spark plug problems, it’s time for a full inspection.
4) Rough Idling
Does the engine shake when stopped? This is a common symptom of poor spark plugs. You might hear irregular noises or feel vibrations that weren’t there before.
5) Sluggish Acceleration
If your car feels slow when speeding up, it may be a sign of bad plugs. You’ll often notice the drop in power more on hills or when merging.
Have a Pro Inspect Your Spark Plugs
Not all spark plug problems are easy to catch without the right tools. A technician can test each plug, check the ignition system, and ensure nothing else interferes with performance. They’ll also look for related issues, like misfires caused by faulty coils or signs of parasitic battery drain that may affect how your engine starts and runs.
Professional diagnostics can also reveal problems that seem unrelated at first. If your car hesitates, shifts oddly, or shows inaccurate readings, a failing speedometer sensor could be involved. Catching these issues early keeps your vehicle running smoothly and helps prevent bigger repairs.
Get Expert Spark Plug Service at Fitz’z Specialists
If your engine’s acting up or your car isn’t driving as it used to, we’re ready to take a look. At Fitz’z Automotive Service, we offer expert automotive electrical repairs in St. Louis, MO. That means we know how to diagnose and fix spark plug issues quickly and thoroughly. We’ll walk you through what we find and handle the replacement with precision.
Whether it’s part of routine maintenance or a deeper inspection, we’re your go-to for clean, complete spark plug replacement and more. Get in touch with us and see how we can help.
