Every internal combustion engine requires a few fundamental elements to function. While your engine won’t work without air, fuel, and proper compression, the spark is the flame that sets the whole process in motion. On a gasoline engine, your spark plugs use an electrical charge to ignite the combustion mixture with each cycle of the engine.
Although you can think of your plugs as the business end of the ignition system, they’re just one part of a much broader array of components. Since ignition issues can lead to a variety of symptoms ranging from no-start conditions to poor idle performance, tracking the ignition issues down can sometimes be challenging. Below you will find just three examples of ignition system failure points on modern vehicles.
1. Spark Plug Failures
Modern cars feature drastically more involved ignition systems than the vehicles of the past, but you’ll still find a humble spark plug at the top of each cylinder. Spark plugs create an arc at their electrode tip that ignites a fuel and air mixture in each combustion chamber. Your vehicle’s performance and efficiency rely on this spark occurring when the piston reaches the very top of its compression stroke.
A spark plug that fails to ignite reliably can cause misfires, poor idle characteristics, rough acceleration, and difficulty starting. Depending on the nature of the failure, these problems may be infrequent at first but worsen over time. Most vehicles will eventually trigger a check engine light once misfires occur frequently enough.
Modern manufacturers typically recommend replacing spark plugs at extended intervals of 60,000 up to 100,000 miles. If your spark plugs fail much sooner than this, then a non-ignition problem may be fouling the electrodes. Frequent spark plug failures are a problem that you should always have a professional shop diagnose.
2. Coil Pack Problems
In the past, vehicles used a distributor and series of wires to provide high-voltage input to each spark plug. Both distributors and spark plug wires were typical maintenance items, so modern distributor-less systems ultimately have fewer potential failure points. These systems also tend to be more efficient than distributor-based ignition systems thanks to tighter computer timing control.
The coil-on-plug (COP) design in most modern vehicles works precisely as the name would imply. Instead of using a distributor to transmit high-voltage from a centralized ignition coil, each cylinder gets an ignition coil of its own. The car’s computer can then directly control the spark timing for each cylinder through these coil packs.
Unsurprisingly, coil pack problems tend to look a lot like spark plug problems. When a coil fails, the plug for that cylinder will not fire or will only fire unreliably. In either case, you can expect the same broad range of symptoms. Most manufacturers do not consider coils to be a regular maintenance item, but they do tend to wear out as most vehicles cross into six-digit mileage numbers.
3. Sensor Issues
Your vehicle’s crankshaft and camshaft position sensors may not seem like a part of its ignition system, but they have a vital role to play. Both of these sensors provide data to the car’s computer that allows it to understand the current position of crucial internal engine components. Since distributor-less systems rely on the car’s computer for proper spark timing, bad data can lead to timing problems.
Fortunately, these sensors will often trigger a check engine light when they fail, making it relatively easy to track down the issue. If left unaddressed, either sensor can cause your car to run poorly, stall, or fail to start entirely. Unlike a bad coil pack or spark plug, a failed sensor can potentially affect the timing of all of your vehicle’s engine cylinders instead of just one.
Modern ignition systems involve a variety of sophisticated and sometimes temperamental components. When one part of the system fails, it can leave your vehicle running poorly or not at all. White’s Automotive Center can help you get to the bottom of any ignition problems and get your car back on the road. Contact us to set up an appointment today!
