What Causes a Car to Stall?

[LucyFitz]

There are several reasons why a car may start and then stall, including clogged fuel injectors and carbon buildup in the throttle body. Fuel injector leakage or clogging: If the fuel injectors inside the engine leak or become clogged, or if there's a circuit malfunction or insufficient fuel injection, they may fail to spray fuel as commanded by the electronic control unit. This can result in an overly lean or rich air-fuel mixture in the engine, causing misfires in individual cylinders and leading to engine stalling. Throttle body carbon buildup: The throttle body regulates the flow of air into the engine. After air enters the engine, it mixes with gasoline to form the air-fuel mixture that powers the engine, functioning much like a valve controlling air intake. During engine operation, a significant amount of exhaust gases is produced, and a small portion of these gases can enter the throttle body. If not cleaned regularly, carbon deposits can accumulate in the throttle body, increasing resistance to its opening and closing. This prevents outside air from entering the engine properly, leading to irregular engine operation and frequent stalling.