What Happens When a Spark Plug in an Audi Fails?

Spark plugs are necessary little components that create the spark of electricity that your car needs in order to start. Without the spark, the combustion chamber could not ignite and your vehicle could not start.

By design, spark plugs transmit an electrical signal from the ignition coil. The timing of this signal is predetermined by the manufacturing standards. The way the spark plugs work is by igniting the air-fuel mixture that is inside the combustion chamber. Spark plugs are not one-size-fits-all. Each vehicle needs a specific type of spark plug.

Just like your motor oil and filters, spark plugs are not designed to last a lifetime. Generally speaking, you should replace your spark plugs about every 30,000 to 50,000 miles. However, there are some newer vehicles with advanced ignition systems that can go for much longer before needing new  spark plugs.

What causes spark plugs to go bad?

Spark plugs are designed to go thousands of miles while enduring the harshest temperatures and conditions. That being said, the stronger the material that goes into manufacturing a spark plug, the more durable and longer lasting it will be. However, as with all automotive parts, the spark plugs do undergo wear and tear over time.

There are two main reasons for spark plugs to go bad: deposit build-up and expanding. Spark plug deposit build-up occurs when deposits from the air-fuel mixture attach to the spark plug. This build-up means your automobile will get an unreliable supply of energy.

An expanding, harder-to-jump gap is another main issue. When a spark plug ignites, the spark has to make it across a gap in the design in order to ensure the perfect level of combustion takes place at the perfect moment. As time passes, this gap widens, usually due to extreme temperatures, debris, and normal wear and tear. If the gap becomes too wide, combustion will be erratic or ineffective.

Below are some of the most common signs that your spark plugs need replacement:

Slow Acceleration

A fault in the ignition system will most likely lead to a slower-than-normal acceleration. However, most of today’s modern engines contain several different sensors that work together. They tell the onboard computer and the ignition system when it is time to send the electric pulses needed to fire up the spark plug. The fault could also be a bad sensor that doesn’t send this signal.

Another cause of slow acceleration could be a worn-out spark plug. As mentioned, spark plugs contain certain materials that work together to produce a spark that is hot enough to ignite the air-fuel mixture. If the spark plug is going (or has gone) bad, then the effectiveness can be significantly reduced along with the acceleration.

Poor Fuel Economy

Burning fuel efficiently in the combustion chamber is one of the roles of a healthy spark plug. When the plugs are working well, it can help your vehicle achieve optimal fuel economy. However, if a plug is not working well, it is often because the gap is either too far apart or too close and can lead to an increase in fuel consumption. Oftentimes, a mechanic can remove a spark plug, correct the gap width, and then put it back in and your vehicle’s issue will be gone.

Engine is Misfiring

A misfiring engine can usually be detected by intermittent stumbling or sputtering noises coming from the engine. The most common cause for an engine to misfire is a malfunction in the ignition system. In most modern cars, it’s likely due to a faulty sensor. However, it can also be damaged by a damaged spark plug wire or tip of a spark plug. The longer you wait to fix the misfiring engine, the worse off the exhaust emissions, engine power, and fuel economy will be.

Surging or Hesitating

A bad spark plug can cause your engine to surge or hesitate. If this is the case, you will notice that your engine seems to hesitate when you accelerate, then there may be a surge in power before your vehicle slows down. If this is happening, there is a high chance that your engine is taking in more air than it should which interferes with the combustion process and power delivery.

Where to Take Your Car to Have Your Spark Plugs Investigated

If you live in Pineville, Charlotte, or Greensboro, NC, bring your Audi to our specialists at A&M Auto Service. We are eager to help you maintain your Audi for its longevity and your safety and enjoyment of your car. Call us today!