Every car has a brake system that drivers use to stop the vehicle while driving. Generally, most brakes should be smooth, given that the driver knows when to use their brakes.
However, you may wonder why your car jerks whenever you brake. We did some digging, and here is what we found out about the matter!
Why Does My Car Jerk When I Brake?
Cars jerk while braking due to an issue with the brake system, such as warped rotors or a failing anti-lock braking system. Beginners who drive manual transmissions may experience jerking while braking because they’re not used to manual transmissions. Plus, slippery floor mats, worn tires, and old brake pads can make cars jerk while braking.
Are you curious to learn more about what makes your car jerk whenever you brake? We looked up the facts, and here is what we learned!
1. Floor Mats
Floor mats are mats on the floor of your car that keep your vehicle clean and protect the floor, but floor mats could also make your car jerk when you brake.
Occasionally, floor mats can slide out of their initial position and interrupt the brake pedal’s function.
When this occurs, your brake pedal will likely not go down smoothly when you press the brake pedal, causing your car to jerk.
Typically, this simply means you have to reinstall your floor mats or replace your floor mats with new ones.
2. Manual Transmission
Driving a manual car will have mild jerks whenever you brake, but the jerks will be more noticeable if the driver is not experienced in driving manual transmission cars.
For instance, cars tend to lurch whenever the driver does not properly shift gears when decelerating and then braking.
Therefore, the driver must learn how to use the clutch pedal, brake pedal, and gear shifter.
3. Warped Rotors
Warped rotors have changed shape, and warped rotors are usually caused by excessive heat, stress, or age.
Additionally, warped rotors can shrink, causing your car to jerk each time you brake since rotors are a crucial part of your brake system.
For instance, you may notice that your car jitters when pushing your brake pedal if the rotors are warped.
4. Worn Tires
Tires eventually get worn over time, especially if you frequently use your car or drive your tires over rough roads.
Additionally, tires can become uneven as some tires wear out faster than others.
As such, worn-out and uneven tires can make cars jerk when braking, especially if the roads have snow, ice, or rainwater.
Generally, the only way to fix uneven or worn tires is by replacing the tires to have completely even and new tires.
5. Problems In The Brake Power Assist
Modern cars have a form of booster system on their brake systems to help power braking,
Power-assisted braking is a design that uses the car’s battery or power to increase the braking power.
Usually, the power assist brake system helps the driver brake easily by amplifying the driver’s input on the car’s brake pedal to safely and smoothly stop the car.
However, a faulty power assist brake system can make the car jerk when you brake, so the power assist brake system would need to be replaced.
6. Damaged Or Old Brake Pads
If you have faulty brake pads, the brake pads could mean that you have a mechanical braking issue that makes your car jerk whenever you brake.
Normally, brake pads can stay good for up to 30,000-70,000 miles of driving, depending on the brand of brake pads you have.
However, the brake pads lose a lot of grips and use over time, so you have to replace the brake pads.
7. Air In The Hydraulic System
Many cars rely on a closed hydraulic loop with a master cylinder that responds whenever the driver uses the car’s brake pedal.
Usually, the master cylinder contains hydraulic fluid that goes through the brake lines to run to the cylinders or calipers.
However, air can enter the hydraulic system, making the brake pedal feel spongy and can cause jerking when you brake.
8. Faulty Anti-Lock Braking System
Many modern cars have a kind of ABS (Anti-Lock Braking System), an electronic control system that keeps your brakes from getting locked up when you do not have traction.
For example, the ABS modulates hydraulic pressure to release and then reapply the brakes quickly if you hold the brake pedal while sliding down an icy road.
That way, you can slow down your car while maintaining your steering control without having to pump the brake pedal.
If your ABS is faulty, the brakes can lock up and jerk, so you need to see a mechanic to have it fixed.
9. Dirty Fuel Injectors
If you notice that your car jerks when you brake and accelerate, the cause will likely be dirty fuel injectors.
Typically, a dirty fuel injector makes your car lose power, causing your car to jerk when you accelerate or brake because there will be an engine misfire.
10. Dirty Air Filters
If your air filters are dirty, there will be less air delivered to your car’s engine, meaning there will be a build-up of soot residue.
Generally, the soot residue can accumulate on various parts of your car, such as the brake system or spark plugs, making your car jerk when you brake.
11. Low Transmission Fluid Levels
Occasionally, you may need to shift gears to brake, but you may notice a hard jerk when you do so.
Generally, this is due to a low transmission fluid level because there is not enough transmission fluid to lubricate the moving gears in the gearbox.
To know more, you can also read our posts on why your car idles high, why your car horn sounds weak, and why your car windows fog up.
Typically, cars jerk when you brake because there is an issue in the brake system, such as old brake pads, warped rotors, or a faulty power brake assist system.
Lastly, other aspects of the car, such as slippery floor mats or air in the hydraulic system, can cause cars to jerk while braking.