We expect our cars to behave in certain ways, and when they don’t it can be very disconcerting. The expectation is that we turn the key and the car starts. When you put it in gear, it drives. And when you step on the brake you come to a stop.
It is never a good feeling when your car stalls. There is a small moment of panic, and then relief when it starts up again. However, a car that stalls is trying to let you know that something needs attention. It is important to figure out what is going on and take the steps necessary to fix it.
You may notice that your car stalls on you while you are braking? What causes this to happen? And what steps should you take to make sure it doesn’t happen again? Let’s take a look.
The answer may seem obvious, but let’s take a closer look into how brakes on a car work.
The brake system in a car is made up of the disk brakes in the front end and/or rear of the car that then connects to a system of tubes and hoses. This braking system works through a master cylinder and when the driver steps on the brake pedal, it actually pushes a plunger against it. This pushing action forces hydraulic oil (or brake fluid) through the tubes and hoses and into the braking unit located on each wheel. Then brake fluid forces the caliper inside the master cylinder to press against the piston. The two brake pads squeeze the rotor attached to the wheel, which causes it to slow down or make a complete stop. The parking brakes, power brake booster and the anti-lock brake system are also connected to the brake system.
A leak in the brake booster can cause the car to stall while braking. This can be caused by a blockage of a vacuum hose or by a cracked, ruptured or leaking diaphragm.
Another reason for stalling while braking is the leaking of brake fluid. This can happen if the master cylinder is leaking brake fluid, either internally or externally.
Another culprit of brake stalling is some kind of brake line obstruction. This obstruction can be caused by rust or debris or even a pinched line.
Air that is present in the brake fluid or line can cause your car to stall when braking. If your system develops a hole somewhere along the line, it can allow air to enter the system. When this happens, there is a drop in pressure when you apply the brakes.
If your anti-lock brake system develops a vacuum leak, expect that your car might stall while you are braking.
If your car should stall while you are braking, you need to find out why. To start, you will need to perform an inspection and use the process of elimination to figure out the cause.
You should first check the car’s transmission. It is a good idea to make sure there is no dirt or debris present. It is a good idea to check fluid levels and clean and replace filters as needed.
You should then check your car’s clutch plate. Check the friction levels and make sure its not too worn down.
It is a good idea to check the relay valves and make sure that your directional signals are not stuck.
The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine.
This valve is controlled by the vehicle’s computer which will adjust idle speed based upon other measurements such as engine temperature, intake air temperature, and electrical system load or voltage.
If your car is stalling, this may indicate a dirty or faulty idle air control valve. In cases where this valve is dirty or failing, your vehicle will stall instead of slowing to idle after the release of the throttle.
A faulty oxygen sensor can cause a host of problems in a car, including stalling. If the air-to-fuel ratio is often, it will have a negative effect on your car’s power, and lead to stalling.
Never underestimate the havoc that bad or corroded wires can cause. Be sure to check wires for signs of damage.
If the wires in your car don’t have consistent, constant, and reliable connection with the ignition circuit, the car can and will lose voltage quickly, and it won’t have the power it needs to keep running as you slow down.
For cars to work efficiently, all of the parts must be in top condition. One tiny part that is worn or blocked, can cause problems in other areas of your vehicle.
Stalling by a car is a way of letting the owner know something is not right. If your car stalls while you are braking, then you need to uncover the problem. A car that stalls while braking can have a few different issues that need to be addressed. In order to figure this out, you will need to do a thorough inspection.
Systematically check under the hood. Check the transmission and make sure fluid levels are optimal. Clean and replace filters as needed. You also want to inspect hoses for any holes. You should also inspect for any damaged or corroded wires.
Stalling is your car’s way of crying for help. Do not ignore this. If you are mechanically inclined, take your time to figure out the root cause.
If you are not comfortable under the hood, please see a professional as soon as possible.