Mini-Course: How to Replace Your Car Spark Plugs.

If your car is starting to run rough, or if you're noticing a decrease in fuel economy, it might be time to change the spark plugs. 

Here's a quick rundown of who should replace spark plugs, what tools you'll need, why it's important to do it, when to do it, and how to do it.

The spark plugs in your car's engine are what create the spark that ignites the fuel and air mixture in the cylinders. Over time, they can become fouled or damaged, which can cause all sorts of problems. That's why it's important to know how to replace them.