Why Does My Car Accelerate When I Apply Brakes?

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Your car will accelerate after pressing on the brake pedal due to any of the following:

  1. Wrong Application Of Pedal
  2. Gearshift Linkage Malfunction
  3. Poor Car Maintenance
  4. Human Error

If your gas pedal sticks on the floor mats or the power train malfunctions, you can see your car accelerate when you try to brake. A stuck throttle body is a major reason why your car uncontrollably and suddenly accelerates during braking.

Since the throttle body is stuck, your vehicle will move even when you apply the brakes. A problem with the throttle body largely causes the car to accelerate after applying the brake.

Another reason you’ll experience unintended car acceleration despite braking is a sticking gas pedal. The accelerator pedal can get stuck to the car’s floor mats for a number of reasons.

What Causes Unintended Acceleration When Braking?

There are a couple of reasons why your car will accelerate when you press down on the brake pedal. You’ll need to track the condition of your vehicle so that you can identify and relate issues as they happen.

The problem could be due to electrical or mechanical malfunction. Wrong application of the brake pedal can also be responsible.

Let’s take a look at how each of these issues causes your car to accelerate when braking.

1. Wrong Application Of Pedal

Your car will unintentionally accelerate if you wrongly apply the pedals. This is a common problem with most cars with multiple pedals. In most modern automatic transmission cars, there are two pedals.

The gas pedal is for acceleration while the brake pedal is used to slow down or stop the car. Sometimes you intend to slow down or stop the car but in error step on the gas pedal. When this happens, you can be sure that the car will unintentionally accelerate rather than the brake.

2. Gearshift Linkage Malfunction

Also called shifting linkage or linkage transmission, gearshift linkage malfunction is an error that occurs mostly with cars running on an automatic transmission. This is a situation in which the gear pedal automatically shifts from parking (P) to drive (D).

The problem occurs when the shifter linkage causes the car to start to accelerate even while your foot is pressing down on the brake pedal.

This is typically due to an electrical malfunction of the cable that connects the transmission to the gear selector or gear shift. While new auto transmission cars lack the lock to resist the shift, older automatic cars are built with a form of lock and resistance.

With the new brake-ignition-shift lock system, drivers cannot possibly start a car without having the gear in P or N.

3. Poor Vehicle Maintenance

Any auto issue can be attributed to poor maintenance. So, it is a no-brainer if you connect an electrical or mechanical malfunction to a lack of vehicle maintenance. This is usually the case when some uncertified or inexperienced technicians conduct trial and error maintenance on your vehicle.

It is important to make sure your mechanics do proper mechanical and electrical work on your car. If they tinker with any of the systems or components, the consequence may be sudden unintended acceleration.

4. Human Error

There are a lot of things the driver can do or engage in to cause sudden unintended acceleration. These activities range from wearing the wrong driving shoes to distraction, drunkenness, loss of concentration, lack of focus, and more.

It doesn’t matter whether they are professional or non-professional, once drivers engage in phone calls, active talks and chats, pressing phone, and lots more, there are higher chances to get distracted and press the wrong pedal.

When Can Unintended Acceleration Occur?

This question is also important and, as I said, you’ve got to track the issue to know when your car always accelerates when you attempt to brake.

Here are possible instances where you can witness unintended acceleration.

  • When you apply brakes.
  • When you disengage from cruise control.
  • When you shift gear.

What To Do If Your Car Accelerates When Braking

While you can prevent unintended acceleration from happening, there are things you can do if you find yourself in its mess. Apart from the mechanical and operation remedies, you can also put in some human efforts by remaining calm and collected when sudden unintended acceleration occurs.

Understandably, when the car is in a dangerous zone like a steep road, the natural thing you’ll want to do is to scamper out of the car for safety. Do not get unstable because the speed of the car might throw you off balance.

Here are operational actions to carry out when you’re face-to-face with the issue:

1. Increase Pressure On The Brake Pedal

Stepping on the brake is the top-of-the-line action to take after realizing that your car is accelerating uncontrollably when you attempt to brake. However, the pressure might not be enough to stop the car.

In this instance, make sure your foot is pressing harder on the brake pedal to exert enough pressure that will be sufficient to brake it. Do not pump the brake pedal but exert a consistent and hard force with the foot. Even if it doesn’t slow down or brake initially, it’ll eventually.

2. Neutral Gear Shift

Naturally, the neutral gear is designed to make the car slow down. So, when you’re in an emergency, especially in the case of sudden unintended acceleration, the most critical thing to do is shift the gear pedal to neutral.

3. Turn Off The Engine

Since no car will move when it’s not ignited – except it’s parked in a steep road – turning the engine will be a no-brainer. Now that the vehicle is in neutral gear, the next line of action is to shut off the engine. You could press the push-starter button –if your car is built with it – before you turn off the engine.

4. Pull Over And Call For Help

Once you have succeeded in bringing the vehicle to a stop, pull it over and call the emergency line for help. If you’re driving an automatic car, return the car to neutral and control it until it finally gets to the side of the road. Remain calm throughout the process.

How To Avoid Human Errors That Lead To Sudden Unintended Acceleration

There’s massive commuters’ distrust of the figures from the Feds, the National Highway Traffic Safety Administration (NHTSA) and other road agencies about the cause of sudden intended acceleration.

While the Feds, for instance, attributed 16,000 cases of sudden unintended acceleration to driver errors, the NHTSA blamed SUA for the incorrect application of pedals.

1. Wear The Right Type Of Driving Shoes

Normally, driving shoes should hold the foot securely to the pedal. Such shoes should have a flat sole and provide adequate traction between the pedal and the foot.

Wearing shoes with adequate grip allows even distribution of force across the surface of the sole and the brake or gas pedal. Also, the shoes should cover your entire foot while allowing freedom of movement for the ankle.

In its report, the NHSTA recommended that drivers should avoid putting on the wrong type of footwear, including soft-sole shoes, high heels, flip-flops, or heavy boots. The NHTSA also advised that drivers should avoid wearing shoes that limit the movement of their ankles while driving.

2. Use Firm Floor Mat

Another human error that may lead to the wrong application of pedal and eventually sudden unintended acceleration is the use of loose floor mats.

As of writing this article, the road agencies have recalled some car models with bad floor mats. Loose floor mats have been identified to be responsible for the accelerator to jam.

3. Be Familiar With Locations Of Car Pedals

Drivers can also prevent sudden unintended acceleration by familiarizing themselves with the locations of both the gas and brake pedals.

4. Avoid Distractions

There is a higher chance of pressing down on the wrong pedal if you get distracted. Pressing the phone, making calls, exchanging banters, or engaging in distracting activities can make you lose focus and stamp on the wrong pedal. Focusing on your driving is the way to go.

Final Thoughts

Uncontrollable acceleration during braking is an issue that can happen to anyone. It doesn’t matter your experience level as a driver or car owner. When it happens that your brake pedal seems like the gas pedal when you press it, it’s not time to get anxious.

Rather, it’s time to ask the all-important question: what causes this to happen and what can I do? Diagnosing and fixing are complementary actions that should naturally follow upon discovering an auto problem.

The primary instance your car will accelerate suddenly is when you try to press down on the brake pedal. You can also see it happen when shifting gear or disengage the cruise control. In any case, you’ve got to take your vehicle to a professional technician.