Signs of Ignition System Trouble

Signs Your Ignition System Needs Service

It can be easy to forget during the day-to-day driving routine how many complex mechanical systems have to work together, just so, for your car to run properly. All these systems serve their own critical purpose, but the ignition system is perhaps one of the most critical.

Knowing what to look for when the ignition system is calling for help is an important step in avoiding bigger problems down the road. Engine misfires, check engine lights, and strange vibrations are all classic tells this system is on the fritz. All of which we’ll cover below, but first, a quick explanation of how your car’s ignition system works.

Just like it sounds, the ignition system is designed to ignite the air-fuel mixture in the combustion chamber. Typically, this starts with the ignition switch getting turned on via a physical key or the more common modern push-button start. Next, the ignition coil receives low voltage from the car battery and converts it to high voltage.

All that juice is sent to the spark plugs to fire off the thousands of explosions happening every minute inside the cylinders. As you might imagine, there is plenty of opportunity for things to go awry with such a complex system.

Which is just one reason electric vehicles (EVs) are so appealing. Along with not having an ignition system with this level of complexity, EVs are just naturally easier to maintain as we cover here. But the overarching theme is that, aside from normal wear and tear items like tires, wiper blades, and brakes, EVs are largely maintenance-free.

Now back to good old internal combustion. Let’s take a look at some common signs that indicate your ignition system needs some TLC.

Check Engine Light

Anytime the check engine light (CEL) comes on, it’s important to pay attention and determine what triggered it. Be aware that some illuminated dashboard warnings can be explained in the owner’s manual like when tire pressure is low. But if it’s a backlit engine icon, it could mean the ignition system needs help.

There are literally thousands of diagnostic trouble codes (DTCs) that can trip the CEL for all manner of vehicle issues. Some are caused by simple-to-fix issues like a loose gas cap. But DTCs to watch out for in this context are related to faulty ignition coils and malfunctioning spark plugs.

Once the CEL comes on, determining the DTC behind it requires a device that can interface with your car’s onboard diagnostic system. If you don’t have one, any auto shop can help, but be sure to ask how much they’ll charge as many garages have a flat fee simply for running the machine to determine the DTC.

Difficulty Starting the Car

If you’re having a tough time starting your car, there are a multitude of potential causes. One common cause is the steering wheel lock being in place. When that happens, try pulling on the wheel in either direction while attempting to start the car until it unlocks.

Another typical issue is the battery has simply died and may need a jump start. But if the car is in fact starting, but is having trouble or seems “off”, it could be the ignition system. A malfunctioning ignition switch could prevent you from turning the key for one thing.

Then there is the possibility of faulty fuel injectors, spark plugs that need attention, or ignition coils due for replacement. In these instances, you may want to talk to a shop about getting your car tuned up to address these issues and save money on bigger problems down the road if left unaddressed.

Unusual Engine Noises

The phrase, “When you know, you know”, is an apt descriptor of your car’s engine making strange new noises. Chances are, under normal operation, you may not even notice the sound your car makes while cruising along. But, when something is wrong, you’ll know.

Strange engine noises are a broad category of potential problems, so let’s zero in on those sounds that might indicate it’s time to service the ignition system.

First up is an engine misfire, sometimes described as a coughing or sputtering sound. Perhaps experienced on start-up, this could mean the ignition coils are on their way out. If you notice jerking motions at speed or under load, this could be an engine misfire caused by malfunctioning spark plugs struggling to deliver a consistent arc.

Then there is the good old engine backfire. Modern coil-on-plug ignition systems with computer-controlled timing have largely eliminated this shockingly loud occurrence. But on older cars with a distributor or in the event fuel combusts somewhere besides the cylinder, you might have a backfire.

It’s a very jarring, and startling loud, occurrence that you can’t miss. Sometimes it’s accompanied by dark exhaust smoke and a strong whiff of gasoline. Regardless of the details, backfiring may mean your car’s ignition system is in need of repair.