Back to all

Low Power Mystery (Ignition Coil Service)

November 22, 2020

It's no fun when your vehicle just doesn't run the way it used to.   You may notice (especially in cold weather) the engine won't start easily or when it does start, it doesn't run smoothly. It may not have much power at all. You also may have had to stop at the gas station more often, a sign your fuel economy isn't what it used to be. 

There could be a few different things that cause those symptoms, but one culprit could be a bad ignition coil. The coil takes the voltage from your battery and multiplies it before that power is sent over to a spark plug. That allows the plug to fire off a good jolt of electricity that ignites the fuel in your cylinder and powers the engine. 

There's usually one ignition coil for each cylinder (or sometimes for a pair of cylinders). If only one of them is not pushing out enough electricity, it can cause big trouble with your engine performance.  Other signs of a bad ignition coil include engine backfire, an oil leak and your Check Engine light coming on.   When that light comes on and you have some of those other signs, you need to have your repair facility check things out fairly soon because you may be damaging your engine and wind up with a far more expensive repair.

A technician will check for a computer code to pinpoint which cylinder is having the problem.  Using other diagnostics, the technician can rule out other components that might be causing the engine to misfire.  Ignition coils usually last 100,000 miles/160,000 km, but other engine conditions can cause them to fail before then. 

Your service advisor may suggest getting all your coils replaced even though only one is malfunctioning. That's probably a good idea in a higher mileage vehicle since the other coils may be close to failure, too. It's also wise to do that if your vehicle's coils are located in a hard-to-reach spot so you likely won't have to spend the money for that labor again when another one fails.

Tuffy Tire & Auto Service Troy
530 E. Maple Rd.
Troy, Michigan 48083
248.585.2770
https://www.tuffytroy.com/

More articles from Tuffy Troy Auto Repair

Bad Vibes (Disc brake rotor problems)

November 9, 2025

If you were to name the most important safety feature on your vehicle right now, what would your answer be? A lot of driving experts would agree that its your brakes. Most newer vehicles use a well-engineered and efficient style of brakes called disc brakes. The name disc brakes comes from one ... More

Catalytic Converter Replacement

November 2, 2025

Many of us have become aware of how important it is to keep our planets air clean, and your vehicle has a key component that helps do just that: the catalytic converter. Its in the exhaust system, and its job is to superheat unburned, harmful byproducts in the exhaust, so they dont get spewed ou... More

Strutting Your Stuff (Shocks and Struts)

October 27, 2025

Ever wonder how your vehicle is able to move over bumps, potholes and other irregularities in the road and you hardly feel a vibration in the cabin? Its your shocks and struts doing the hard work along with the rest of your suspension and tires. They keep the ride smooth and are important for yo... More