What Causes the Engine to Stall When Accelerating?

[SanWyatt]

Reasons for engine stalling when accelerating: 1. Dirty throttle body with contaminants: This condition reduces or causes the throttle plate to stick during acceleration, leading to stalling. The solution is to clean or replace the throttle body and perform throttle matching. 2. Faulty ignition coil, open or short circuit: For ignition coil troubleshooting, when visual inspection and resistance measurement fail to provide accurate diagnosis, replace with a new ignition coil. 3. Clogged fuel filter: Restricted fuel flow during acceleration. Replacing the fuel filter resolves this acceleration stalling issue. 4. Faulty mass air flow sensor: Requires replacement. 5. Fuel pump malfunction.

[VonDaniel]

I've been driving for several years and have encountered the annoying issue of the engine stalling when stepping on the accelerator. Back then, it was due to a faulty fuel pump, causing insufficient fuel supply—when I pressed the throttle, the engine couldn't get enough fuel and naturally stalled. It might have been related to fuel quality; using substandard gasoline could clog the fuel lines and cause poor fuel injector performance. Another possibility is a dirty throttle body with too much carbon buildup, affecting airflow. I remember that time on a suburban road when the car suddenly stalled—it almost caused an accident. Later, at the repair shop, they diagnosed it as a faulty ignition coil causing unstable ignition. It's best to clean the fuel system regularly and use quality gasoline. If this happens, pull over safely first, check fuel pressure and the air filter, and don't ignore it—safety comes first.

[Shirley]

This situation is quite common, and I personally feel it's mostly caused by a faulty idle control valve. When you press the accelerator, the engine needs to balance air intake and fuel supply, but if the valve gets stuck or the sensor fails, it can stall. It could also be due to a vacuum hose leak, causing an imbalance in the air-fuel mixture. Last time I had my car repaired, the mechanic mentioned it could be related to aging spark plugs; insufficient spark can make the engine more prone to stalling when accelerating. For a preliminary self-check, observe whether the idle speed is stable and listen for any unusual engine noises. I recommend addressing this promptly because after stalling, both braking and steering may fail, which is especially dangerous in traffic jams. Simply put, don't delay—have a professional check the electrical and fuel systems.

[BrodyMarie]

When I first started driving, I was always worried about stalling when stepping on the gas pedal, thinking the car was broken. A friend told me that it might be because the air filter was too dirty and clogged, preventing the engine from getting air and causing it to shut down; or the throttle position sensor could be faulty, sending inaccurate signals and leading to uncontrolled fuel supply. Don’t just focus on the fuel system—loose wiring connections could also cause a short circuit. I once cleaned the filter myself, and the problem improved, but don’t force it—it’s safer to call a tow truck for a proper inspection. After all, if the car stalls, it won’t move, which is a real hassle.