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Why Do My Brakes Feel Spongy?

September 2, 2018

Your brakes are a complicated system on today’s cars and there are many reasons why they may not feel like they are performing as they should. In this short blog, we want to tackle why your brake pedal may not feel like it should while braking.

First, let’s chat about how a common brake system works and what components are in the system. Most systems are hydraulic with some sort of air vacuum booster. For the simplest description of how they work, when you press on the brake pedal the booster helps the driver apply hundreds of pounds of pressure to the hydraulic components. The hydraulic system, (brake master cylinder) pushes fluid down towards the brake calipers and wheel cylinders via the brake lines. The pistons within these components are what apply the brake pads and or shoes to the rotating brake disc and brake drums. When you release your foot from the brake pedal, the booster relieves pressure to the master cylinder and fluid is allowed to return back to the brake fluid reservoir.

Why are brakes hydraulic and not air? Hydraulic systems are great for hundreds of pounds of pressure without compressing and losing the pressure. If the air was used instead of hydraulic, the air would compress easily as it would if you pressed on a balloon. Hydraulics allow tremendous pressures to be applied without compressing.

A common symptom of a failed brake component is a spongy brake pedal. Most of the time this represents a hydraulic problem. There is a compromise in your brake hydraulic system causing it to leak brake fluid out and allowing air to get into the system. This will cause a fading brake pedal and is often described to the auto repair shop as a spongy brake pedal. While you push down on the brake pedal instead of all the pressure going to the brake pistons some will leak out and you will experience a pedal that goes to the floor. When releasing the brake pedal on a leaking system the returning motion will suck in air. Once the air is introduced to the system the brake hydraulics are no longer able to create the needed pressure to apply your brakes!

Another cause of a spongy brake pedal is sticking brake slides, pins, and other moving parts. Your brakes are only millimeters away from the braking surface under normal operation when the brake is applied. This short-travel allows for quick and smooth operation. If one of the pins in the brake caliper is stuck when you apply the brakes it will have longer to travel causing late braking and a spongy pedal. These moving parts should be inspected regularly and lubricated to help keep this from happening. Whenever a brake job is completed these parts should be either replaced if they are worn or if they are still in good shape, they can be cleaned and lubricated, and reused. Your automotive shop can help you decide the right action to take.

Most likely your car will be equipped with some sort of ABS (Anti-Lock Brake System.) Most modern cars come equipped from the factory with this benefit. When your ABS system malfunctions are can also cause a spongy brake pedal. Your ABS system is designed to allow the driver to maintain more control of the car in a high-speed stop. By measuring the wheel speed of each wheel when you are in a panic stop situation the ABS computer controls the brakes to keep the tires from locking up. Your ABS does this by releasing brake pressure on that wheel. This is important because a skidding wheel has less friction against the road surface and not only stops a car-less quickly but will not allow a driver to control the direction of the car. When your ABS malfunctions it can cause the brake pressure in the system to be released, and as the driver, you may feel very strange sensations with your brake pedal. Vibration, spongy pedal, the pressure pushing back while you are applying the brakes, can all be described. If you are feeling one of these sensations, see your automotive shop as soon as possible.

Recently we had a vehicle at Casey’s Automotive that had a sinking spongy pedal. After checking over the brake system we found the brake booster had failed. Usually when a brake booster fails you will experience a very hard pedal because the booster is not able to give you the assist it is designed for. This vehicle however was experiencing the opposite. When applying the brake pedal the brake pedal would sink and the vehicle was not easy to stop. The brake booster was full of fluid, destroying the inner diaphragm.

Bottom line cars a very complicated pieces of equipment. Your brakes are arguably one of the most important safety features and for best operation and safety you should have them checked at regular intervals and serviced when needed. It is our professional opinion at Casey’s Automotive brake problems should never be left unchecked. As soon as you feel a spongy brake pedal or any other braking abnormalities, take it in for service immediately.

Drive safe and happy motoring!

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Why Regular Oil Filter Replacement is Crucial in Sterling, VA

March 19, 2025

At Casey’s Automotive in Sterling, VA, we know how important it is to keep your vehicle running smoothly, and one of the simplest yet most critical maintenance tasks is regular oil filter replacement. Your car's engine is made up of hundreds of moving parts that need proper lubrication to function efficiently. The oil filter plays an essential role in this process, helping to ensure that the oil circulating through the engine stays clean and free from contaminants. In this blog post, we’ll explain why regular oil filter replacement is so important, how it impacts your vehicle’s performance, and why Casey’s Automotive in Sterling, VA is your trusted source for quality automotive care. What Does an Oil Filter Do? The oil filter is a small but mighty component in your vehicle. Its primary job is to remove contaminants from the engine oil, which can accumulate over time as your engine runs. These contaminants can include dirt, metal particles, carbon, and other debris that can damage sensitive engine parts. By filtering out these particles, the oil filter ensures that the oil remains clean and effective in lubricating the engine, reducing wear and tear. However, as the oil filter captures more contaminants, it can become clogged and lose its effectiveness. When this happens, the oil can’t flow freely through the engine, leading to decreased lubrication and potential engine damage. That’s why regular oil filter replacement is crucial for maintaining your car’s performance and longevity. The Benefits of Regular Oil Filter Replacement 1. Enhanced Engine Protection Your vehicle’s engine is its most important and expensive component. The oil filter is your first line of defense against contaminants that could cause significant engine damage. By replacing the oil filter regularly, you ensure that your engine is always getting clean, fresh oil, which keeps it running smoothly and efficiently. At Casey’s Automotive in Sterling, VA, we recommend oil filter replacement every time you change your engine oil, which typically happens every 3,000 to 7,500 miles, depending on your vehicle’s make and model. Regular oil changes, including a fresh filter, help preserve your engine’s health and prevent costly repairs down the road. 2. Improved Fuel Efficiency Dirty or clogged oil filters can reduce your engine’s efficiency, leading to decreased fuel economy. When your oil filter is blocked, the oil has to work harder to circulate through the engine. This means the engine has to work harder as well, which can cause a drop in fuel efficiency. Replacing the oil filter ensures optimal oil flow, improving fuel efficiency and helping you get more miles per gallon. As a trusted auto shop in Sterling, VA, we understand the importance of fuel efficiency for our customers. With regular oil filter replacement, you can keep your car running efficiently and save money on gas. 3. Prevents Engine Overheating When the oil filter is clogged, it can cause the engine oil to become thicker, which makes it harder for the oil to circulate properly. As a result, your engine may overheat due to inadequate lubrication. Overheating can lead to severe damage to engine components, such as warped parts or seized engines. Regular oil filter replacement helps prevent overheating by ensuring that oil circulates freely and efficiently. At Casey’s Automotive , we always check your oil filter during routine maintenance and provide expert guidance on when it’s time for a replacement. 4. Longer Engine Life The cleaner your engine oil is, the longer your engine will last. A clean oil filter ensures that harmful particles don’t build up inside the engine, which can contribute to wear and tear on moving parts. By replacing the oil filter regularly, you are extending the lifespan of your engine and avoiding premature engine failure. We believe in proactive maintenance at Casey’s Automotive , and regular oil filter replacement is one of the best ways to avoid costly repairs and maximize your vehicle’s longevity. How to Know When It’s Time for an Oil Filter Replacement Most vehicles require an oil filter change at the same time as an oil change, but it’s always a good idea to be aware of the signs that your filter may need attention. Here are a few indicators that it may be time for an oil filter replacement: Check Engine Light : If your check engine light comes on, it could be a sign that the oil filter is clogged or that there is an issue with the oil circulation in your engine. Strange Engine Noises : If you hear knocking or grinding sounds from your engine, it could be caused by a lack of lubrication due to a clogged oil filter. Reduced Oil Pressure : A drop in oil pressure could indicate that the oil filter is clogged and preventing proper oil flow. Dirty Oil : If the oil looks dirty or sludgy even after an oil change, it could mean the oil filter isn’t doing its job effectively. If you notice any of these signs, schedule an appointment at Casey’s Automotive in Sterling, VA, as soon as possible. Our team of experts can inspect your oil filter and perform any necessary maintenance to keep your vehicle running smoothly. Why Choose Casey’s Automotive for Your Oil Filter Replacement in Sterling, VA? At Casey’s Automotive , we’re committed to providing the highest quality service to our customers in Sterling, VA. Our team of skilled technicians is equipped with the knowledge and tools to perform oil filter replacements quickly and efficiently. We only use high-quality oil filters to ensure that your engine remains protected, and we provide honest, transparent recommendations based on your vehicle’s specific needs. Regular maintenance is key to the longevity of your vehicle, and oil filter replacement is one of the most important steps you can take to protect your car. Whether you’re due for an oil change or need an inspection, our team is here to help. Schedule Your Oil Filter Replacement Today Don’t wait until it’s too late—schedule your oil filter replacement at Casey’s Automotive in Sterling, VA, today. With our reliable service and expert advice, we’ll keep your car running at its best for years to come.

Improve Fuel Efficiency in Chantilly, Sterling & Great Falls | Casey’s Automotive

Common Automotive Repair Mistakes and How to Avoid Them | Casey's Automotive in Chantilly, VA, Sterling, VA & Great Falls, VA

April 29, 2024

Learn to avoid common car repair mistakes with Casey's Automotive in Chantilly, Sterling, and Great Falls, VA. Top-notch advice and services. Schedule an online appointment now!