What Causes a Car to Stall When Braking?

[OMalachi]

The reasons why a car stalls when braking are: 1. Component failure: The ignition coil, capacitor, or electronic ignition module may initially start the car, but after a while, the engine stalls, then restarts, and stalls again. This requires repair at a maintenance shop; 2. Circuit failure: The car stalls due to low-voltage power interruption while driving. It is necessary to check the ignition and starter switch, as well as the fuse box; 3. Low-voltage circuit short circuit: In this case, the car stalls intermittently, and the low-voltage circuit needs to be inspected; 4. Ignition system: Engine overheating or issues with the anti-explosion system can cause stalling. Driving time should be reasonably arranged; 5. Idle speed set too low may also lead to stalling, requiring recalibration of the idle speed.

[MacLane]

My car had the same issue last year, it would stall when I hit the brakes, which made me quite nervous. It turned out there was a vacuum system leak, causing the engine to lose power during braking. The vacuum hose had aged and loosened, allowing air to enter and affecting the idle. Also, the idle control valve was stuck due to excessive carbon buildup. I checked the brake booster—if that thing fails, it can also affect the vacuum. Later, at the repair shop, the mechanic said common causes also include clutch or torque converter issues, especially in manual transmission cars. I suggest you park in a safe place first and check for cracks at the vacuum hose connections, or just head straight to a professional repair shop for diagnosis. Driving like this is dangerous; brake failure would be disastrous.

[MacBriella]

Having driven a taxi for so many years, I've encountered this situation quite a few times. The most common causes for stalling when braking are issues with the idle control valve or problems in the fuel system, such as a clogged filter or unstable fuel pump operation. Additionally, abnormal torque converter lock-up in automatic transmissions can also lead to stalling. As a driver, I'd recommend first inspecting the engine bay for any unusual noises or signs of oil leaks, especially around the vacuum booster. Regular maintenance of the idle control valve can prevent this issue and save on repair costs. From a safety perspective, this problem shouldn't be delayed. If the engine stalls and isn't controlled properly, it's easy to rear-end another vehicle or cause an accident. It's best to take it to a reputable repair shop immediately.

[VonMatthew]

My friend's car kept stalling when he pressed the brakes recently. As a novice driver, he doesn't know much about cars. We suspect it might be a fuel system issue, like low fuel pump pressure or sensor failure, or possibly air entering the intake pipe affecting the engine. Simply put, it's like a computer crash where the control unit receives wrong signals. We advised him to try changing the filter or just take it to a 4S shop for inspection. This kind of problem is really annoying, so he needs to be extra careful when parking to avoid it happening on the highway.