Back to all

Low Power Mystery (Ignition Coil Service)

December 24, 2023

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 Homer Glen
15743 S Bell Rd
Homer Glen, Illinois 60491
708-301-8885

More articles from Tuffy Homer Glen

The Light Nobody Wants to See (Check Engine Light)

April 28, 2024

You've probably had your Check Engine Light go on. Then it goes off and you figure, hey, whatever the problem was, it's gone now and I don't have to worry about it. Well, the problem may have gone away and it may not have. Your vehicle likely has one of these warning lights on the instrument pa... More

Losing Your Cool (Why is My Air Conditioning System Not Working?)

April 21, 2024

When you turn on the air conditioning in your vehicle, you expect cool air to come out of the vents. You depend on it, especially in hot weather, but it can also be important in humid weather when you need it to help defrost your windows and windshield. The air conditioning system has a lot of p... More

Snake in the Engine (Serpentine Belt)

April 14, 2024

There's a belt that snakes through your engine. It's even named for a snake, the serpentine belt. It'll bite you when it breaks, possibly leaving you stranded. So, it's good to know a little about this snake-like belt. In early engines, there were lots of belts. They were used to convert the r... More