That little engine part called the spark plug performs a huge job in delivering a vehicle’s power, performance, dependability and fuel efficiency and, according to the non-profit Car Care Council, should be replaced periodically.

“Spark plugs are one of the hardest working parts of a vehicle. A spark plug can fire 400 times per minute per cylinder or 1,600 times a minute on a four-cylinder engine,” said Rich White, executive director of Car Care Council. “Many car owners delay spark plug repair on their vehicles, even after they have failed. This is a mistake since fouled, damaged or worn out spark plugs can lead to engine damage, reduced fuel efficiency and poor performance like misfiring, hard starting and sluggish acceleration.”

If a customer comes to you citing any of the following symptoms, the Car Care Council recommends having the vehicle checked to prevent more costly problems from developing:

• Rattling, pinging or knocking noises. When spark plugs begin to misfire, you may notice unusual noises from the force of the pistons and combustion not working properly. Pistons travel at high velocities; if the spark plug fires at the wrong time, this could lead to constant rattling, pinging or knocking sounds. 
• Hard vehicle start. If your car is having trouble starting or just feels disjointed and jerky, your spark plugs may not be working right. This can lead to misfires and erratic performance. 
• Reduced performance. Spark plugs fire when you accelerate and change gears. If the spark that the plug generates isn’t functioning at 100 percent, your vehicle performance will be poor, and you’ll experience a sluggish and fuel-wasting drive. 
• Poor fuel economy. Lots of things can lead to poor fuel economy. In the case of old spark plugs, fuel is wasted because your vehicle fails to receive the proper, heat-generating spark at the right time.

The Car Care Council recommends that consumers consult their owner’s manual for the vehicle manufacturer’s recommended spark plug replacement intervals. The council also recommends replacing all of the plugs at the same time and with the same type of spark plug that the vehicle was originally equipped.

“Replacing spark plugs is a relatively inexpensive maintenance task and can be performed by a do-it-yourselfer or by a professional technician at any auto repair shop,” said White.