Spark plugs are small but critical components in your car's engine that ignite the air-fuel mixture to create the combustion needed to power the vehicle. Essentially, they are the starting point for your engine's operation. When you turn the key, the ignition system sends a high-voltage electrical current to each spark plug. This current jumps a small gap at the plug's tip, creating a spark. This spark ignites the compressed mixture of air and fuel within the combustion chamber, causing a controlled explosion that forces the piston down and turns the crankshaft.
A typical four-cylinder engine has four spark plugs (one per cylinder), while a V6 has six, and so on. They are threaded into the cylinder head and must withstand extreme heat and pressure. Over time, spark plugs wear out. The electrodes erode, which widens the gap and makes it harder for a strong spark to form. This leads to common engine problems like rough idling, difficulty starting, reduced acceleration, and a noticeable drop in fuel economy.
For most cars, spark plug replacement is part of routine maintenance. The interval can vary significantly based on the type of plugs installed.
| Spark Plug Type | Typical Replacement Interval (Miles) | Key Characteristics |
|---|
| Copper/Nickel | 30,000 | Most basic type, affordable, shortest lifespan. |
| Platinum | 60,000 - 100,000 | Better durability and performance than copper. |
| Double Platinum | 100,000 | Improved design for waste-spark ignition systems. |
| Iridium | 80,000 - 120,000 | Longest lasting, best performance, most expensive. |
Using the correct spark plugs specified for your vehicle is crucial for optimal engine performance, efficiency, and emissions control.
