Back to all

Plugging Away (Spark Plug Replacement)

July 2, 2023

If you drive a vehicle with a gasoline engine, thank the spark plugs for igniting the gasoline/air mixture in each cylinder that keeps your vehicle traveling smoothly down the road every day.  Your spark plugs work hard, firing thousands of times in a well-choreographed order, and you usually don't pay much attention to them until one of them stops working the way it should.

Signs that spark plugs are wearing out include:

  • Engine runs more roughly than it did
  • Vehicle doesn't start as easily as it used to
  • Vehicle hesitates when you press on the accelerator
  • Your fuel economy has gotten worse

When a spark plug stops working altogether, you will find your engine has likely lost a lot of its power and isn't running smoothly.  Your Check Engine light may  come on.  Then it's time to head to come to our service center to have it diagnosed.

If your plugs need to be replaced, they're usually done all at the same time. And if your vehicle has spark plug wires, experts recommend you change them as well. Different type of spark plugs last longer than others, and your service advisor can discuss what's best for your vehicle and driving habits.

A technician will also determine if there are any carbon deposits on your plugs, how healthy the ignition coil is (it's the part that supplies the high-voltage jolt that makes the spark) and will look for other signs and symptoms that may point to other problems in your engine. For instance, if a spark plug is fouled by oily deposits, it's possible oil is getting into the combustion chamber. 

They will also check all the plugs to see if there are problems in just one or all cylinders.  Sometimes a technician will find a plug that has overheated, literally melting the metal.  In that case, they may recommend they correct that problem before replacing the spark plugs.

Most spark plugs will last for a good, long time.  Even if you aren't seeing any symptoms they're wearing out, make sure you have your service advisor check your vehicle manufacturer's recommended maintenance intervals.  Preventative maintenance will keep your vehicle running reliably so you can count on it to get you where you want to go. 

Commerce Auto Repair
9575 Commerce Rd.
Commerce, Michigan 48382
248.363.3749

Need Service?

Request a Quote

More articles from Commerce Auto Repair

Power Steering Pump Replacement

January 25, 2026

When youre driving and you hear a squeal or groan when you turn, it may be a sign your power steering pump is on its last legs. The same is true if you feel your steering is slipping or doesnt respond to your hands like it used to. Precise, responsive steering is, of course, important when it ... More

10 Things That Are Lowering Your Fuel Economy

January 18, 2026

Regardless of whatever current gas prices may be, if you could use less gas, wouldnt you? Well, here are 10 things that are robbing you of better fuel economy that you can change for the better: Not enough air in your tires. Underinflated tires have a smaller rolling diameter and more res... More

Don?t Meddle with the Pedal (Brake Caliper Replacement)

January 11, 2026

If you drive a newer vehicle, chances are it has disc brakes, and one of the components of that type of brake is called a brake caliper. The caliper allows the pressure from your foot on the brake pedal to eventually move brake pads against discs in your wheels, which then slow and stop your veh... More