What Causes A Car To Backfire?

What Causes A Car To Backfire?

| By: Christian Brothers Automotive

The exhaust system seems to raise more concern than any other part of the car. At our car shop near Sunset Valley, we want you to have peace of mind on every drive.

Has your car been backfiring? It can often sound like a gunshot, if not a “cough” or a “sputter”. While an engine backfire (or “afterfire”, if it occurs when the engine has already been shut off) will not harm your vehicle, it can be inconvenient and interrupt any peaceful drive.

So why has your engine been backfiring? And how do you keep the problem from happening again? Today, our ASE-certified technicians explain why your car backfires and what it means.

What causes an engine to backfire?

Usually, a vehicle’s will backfire through the exhaust because the engine is decelerating too quickly. However, there are several possible causes.

A few reasons your exhaust could be backfiring:

  • Your engine decelerated too quickly
  • Your gasoline contains high levels of alcohol
  • High engine temperatures

Another possible reason for your backfire is a spark plug refusing to “spark” when the exhaust valve opens. If the air/fuel mixture has become too rich, unburned fuel is left in the exhaust system. The misfired spark plug ignites the rich air/fuel mixture, causing a loud “bang” in the tail pipe.

When your car is brought into our San Antonio auto shop for service, we’ll let you know why the exhaust is backfiring.

How do I keep my engine from backfiring?

A backfire is loud and intrusive. Fortunately, there are a few ways to cure an overactive exhaust tailpipe.

A few ways to stop a backfire include:

  • Lowering the engine speed gradually
  • Changing fuel brands to one with lower alcohol levels
  • Adjusting the carburetor to lower engine temperatures

If the cause of the backfire is a rich air/fuel mixture, speak with our specialists about increasing your air volume. The expert technicians at our auto shop in San Antonio can relieve some of the airway’s constriction, increasing the engine-cooling air volume and minimizing the risk of a backfire.

Schedule exhaust system service with our San Antonio auto shop

While a backfire from the exhaust pipe won’t hurt your car, it can be scary and intrusive. Ensure your vehicle is operating as it should by calling to schedule an exhaust system inspection at Christian Brothers Automotive Alamo Heights in San Antonio, Texas today.

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