Everyone appreciates it when their brakes work, but car brakes too sensitive may make for a very uncomfortable ride for you and your passengers. This is because brakes are used not just to stop the automobile but also to slow it down. If your automobile comes to a complete stop every time you slow down at a corner, you may be putting yourself and others on the road at risk.
Excess brake fluid leaks from the reservoir, putting pressure on the caliper pistons and making the brakes overly sensitive. Brake sensitivity can also be caused by contaminated brake pads and rotors; anything from transmission oil to brake fluid can seep into the brakes and cause your brake pads to wear out prematurely.
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Reasons Why Car Brakes Too Sensitive?
There are several issues that can cause your brakes to become a little too sensitive, and sometime they will require a visit to your brake repair shop.
- Brake fluid is overflowing
- Contaminated pads and rotors
- Pads that have disintegrated
- Calipers that aren’t working properly
- Brake lines with flaws
- Clogged master cylinder
- Brake booster failure
- Out of adjustment brake pedal rod
- Brake controller failure
You’ll learn about the most prevalent causes of brake sensitivity, how to identify them, and how to fix them in this article.
1. Brake Fluid Is Overflowing
Brake fluid grows slightly in volume when it heats up. When the brake fluid reservoir is filled and the reservoir cap is securely fastened, the fluid has only one destination. It slightly pulls the caliper pistons out, just enough to free up the free-play.
If the surplus fluid in the reservoir is not emptied, then it makes the car brakes too sensitive.
Diagnose: If the fluid reservoir is overfilled, use a siphon to drain some of the fluid while being careful not to contaminate it
2. Contaminated Pads And Rotors
Braking may become sensitive due to pad or rotor contamination. Fluids such as braking fluid, coolant, diesel, gas, power steering, transmission, gear oil, and others can break down the pad material. Hot patches on the rotors, as well as corroded, pitted, or abrasive metal, can cause the brakes to bite hard.
Diagnose: Remove the brake pads and inspect for oil contamination; inspect the rotors for corrosion, elevated or rough surfaces, cracks, warping, and hot spots, among other things.
If the rotors are within spec, they can be refaced or replaced with pads.
3. Pads That Have Disintegrated
A bad brake pad is a common issue in older cars that don’t get much use. The backing plate separates from the braking material due to corrosion. The substance might become stuck in the rotor, producing gripping and sensitive braking.
Diagnose: Remove the calipers and pads and inspect for separation; if required, replace them.
4. Calipers That Aren’t Working Properly
When it comes to braking, calipers handle all the heavy lifting. Calipers that aren’t working are also prevalent. Corrosion on the caliper piston might bind, locking the pad against or close to the rotor.
Braking force can be amplified by touching the brakes.
Diagnose: If the pistons do not retract when pushed back into the caliper with a screwdriver, the caliper may be partially seized. However, we’ll need to examine the brake hose to be sure.
5. Brake Lines With Flaws
The flexible brake cables transfer fluid pressure from the master cylinder to the dynamic suspension and caliper. With age, you can expect cracked and perished hoses and corroded metal fittings. The hoses also fail on the inside.
The rubber peels away in strips and frequently works as a one-way valve, allowing fluid pressure to enter the caliper but not all of it to exit. As a result, the brakes are only partially engaging, making them extremely sensitive to further application.
Diagnose: Perform the caliper test and if the caliper piston does not move, open the bleed nipple.
If the piston is retracting, the brake hose will break, and you should replace all four brake hoses.
If the piston still won’t retract, the caliper is defective; you should replace calipers in pairs on the same axle.
6. Clogged Master Cylinder
To apply brake pressure to the four calipers, the master cylinder uses two independent pistons and seals. Typically, the two different brake lines are paired diagonally.
- Front left and rear right, Port 1
- Front right and rear left, Port 2
Master cylinders which are crucial brake components ensure the safety of the occupants and other road users. They have a unique design and rarely cause any issues.
However, the master cylinder’s compensating ports may become blocked, preventing the brakes from fully releasing. The small ports might become clogged due to disintegrating components and polluted liquids.
Diagnosis: Remove the reservoir cap and have a friend pump the brakes frequently. As the fluid rushes back into the reservoir through the compensating ports, splashing should be visible inside the reservoir.
7. Brake Booster Failure
Between the brake pedal and the master cylinder is the Servo. To lessen foot pedal effort, it uses an engine vacuum. A rubber diaphragm separates two chambers in the Servo. The drivers only need to apply minimal pressure to apply brakes since the engine suction lowers the pressure on one side of the servo. The pedal will return to its resting position via an internal spring and an atmospheric valve.
Diagnose: Start the engine after pressing the brake pedal multiple times. The pedal should be slightly lowered. Release the pedal and make sure it returns to its original position.
8. Out Of Adjustment Brake Pedal Rod
The brake rod connects the foot brake and the master cylinder mechanically. The rods are adjustable in some cars and require a certain amount of free play. The brake pedal to master cylinder free-play is affected by adjusting, changing, or swapping out rods, pedal boxes, master cylinders, boosters, or modifying the thickness of the firewall.
Diagnose: Check to see if your car has a brake pedal rod that may be adjusted. Look for free play
9. Brake Controller Failure
Active braking will be used in higher-end vehicles. The sensors detect an emergency by measuring the speed at which the brakes are applied. Another sensor assesses whether the brake pedal is pressed hard enough by measuring brake pedal pressure. If the controller determines that it hasn’t, it taps into a reserve of energy to provide more power to the brakes leading to the car brakes being too sensitive.
Diagnose: Each brake controller has its control module. Check for problem codes with a code reader.
Conclusion
If your car brakes too sensitive and there are any of the following indicators indicating that your brakes require expert repair, don’t delay. If you ignore minor concerns like worn brake pads, they can be rather expensive. Having a properly functioning brake system is, of course, essential for your safety.