How To Tell If Your Car Has Bad Spark Plugs

Do you have a suspicion that your vehicle's spark plugs need to be replaced? If so, you'll want to know what warning signs to look out for.

Engine Light

An easy way to tell if you have bad spark plugs is if the engine light on your dashboard turns on. This light has a code associated with it, and a mechanic can plug a computer into your vehicle to read the code that has triggered the light. In addition, many auto parts stores offer this service as well. It may tell you right away that the problem is with the spark plugs so you can avoid unnecessary troubleshooting.

Rough Idling

Another way to diagnose your bad spark plugs is to see how your vehicle behaves while it is idling. You're likely used to what your car feels like when the engine is turned on and the car is in park. If you notice that the vehicle is now shaking a bit while you're not moving, it is a problem that is likely caused by the spark plugs malfunctioning. 

Low Gas Mileage  

Your spark plugs are not going to produce that spark that your engine needs to operate, which can result in the vehicle simply using more gas than normal. If you've noticed that you're filling up your gas tank more often than normal and you are not traveling more, swapping out the spark plugs with new ones could be the solution to your problem.

Lack Of Power

Does the engine feel like it doesn't have the same power that it used to when you accelerate? This can be caused by bad spark plugs as well. A V6 engine is going to have 6 spark plugs, and a V8 engine is going to have 8 spark plugs. Having some of those spark plugs stop working properly will naturally result in a decrease in power as you accelerate. 

Difficulty When Starting

Bad spark plugs are also going to cause problems when you go to start your vehicle. You may discover that the car turns over a lot before it finally starts up, or you have trouble starting it up in general. This is because the engine isn't getting the spark that it needs. One bad spark plug may cause some difficulty starting up, while multiple bad spark plugs will make it very hard or impossible. 

Reach out to an auto repair shop if you are having problems with your vehicle's spark plugs.