Back to all

A Bright Spark (Ignition Coil Replacement)

January 5, 2025

Ever wonder how your vehicle’s engine is able to take the 12-volts from its battery and ramp that up to as high as the tens of thousands of volts it takes to fire its spark plugs? The secret is something called an ignition coil.  Most newer vehicles have an ignition coil at each cylinder, but older ones have a coil that serves all of the spark plugs. 

There are telltale signs that you have an ignition coil problem.  As you might expect, one symptom is it’s hard to start your engine or it won’t start at all.  If your engine is misfiring or not running smoothly or you see the Check Engine light come on, those all could point to an ignition coil failure.

Several things can contribute to ignition coil trouble in addition to normal wear and tear. Moisture and dirt may have gotten inside the coil, plus the heat and vibration of your engine over time can contribute to them going bad.  Bad spark plugs or plug wires can also be a cause.  

While ignition coils can last 100,000 miles/160,000 km, depending on how you drive and in what conditions.  If you start noticing some of the signs and symptoms just described, it’s a good idea to schedule a visit to see us so a technician can diagnose what’s wrong. Driving too long with an engine misfiring can damage your catalytic converter, and that can be expensive to replace.

A technician will thoroughly check your ignition system and determine where the failure is.  If it’s only one coil that’s bad, it may be the only thing that will need replacing.  If your vehicle has a distributor, it may also need to be replaced.  Properly-working ignition coils will help your vehicle operate at its best and help prevent future engine damage.

Tuffy Joliet (South Plainfield)
2031 SR 59
Joliet, Illinois 60586
815-436-1829

More articles from Tuffy Joliet

Ball Joint Replacement

February 22, 2026

Think about this the next time youre driving. Your front wheels can steer your vehicle and, at the same time, the wheels can move, even with all the irregularities in the road moving them up, down and in different directions. Pretty amazing engineering, wouldnt you say? What allows that are part... More

What?s That Yellow Squiggly Line Anyway? (What Warning Lights Mean)

February 15, 2026

You may have noticed when you start your vehicle, youll see several symbols light up on the dash. Theyre different colors and shapes, and sometimes its hard to figure out what each of those symbols mean. They are warning lights and symbolize something in your vehicle is sending you a message. I... More

No Fueling Around (Fuel Filter Replacement)

February 8, 2026

A driver called in to the shop the other day saying his European sports sedan had an odd problem. He was driving when his car started to slow down. Applying more throttle didn't help. He pulled over to the side of the road, shut the engine off and waited a few minutes before starting it up aga... More