The IAC valve controls the amount of air that bypasses the throttle body when the engine is idling. If the IAC valve is faulty, it can cause the engine to stall when put into drive. The engine may also idle roughly or stall when coming to a stop.
2. Throttle Position Sensor (TPS) issues
The TPS tells the engine control unit (ECU) how far open the throttle is. If the TPS is faulty, it can send incorrect signals to the ECU, which can cause the engine to stall. The engine may also hesitate or surge when accelerating.
3. Faulty fuel injector
A faulty fuel injector can cause the engine to stall because it is not delivering the correct amount of fuel to the engine. The engine may also run rough or have a loss of power.
4. Vacuum leak
A vacuum leak can cause the engine to stall because it is allowing unmetered air into the engine. The engine may also run rough or have a loss of power.
5. Faulty ignition system components
Faulty ignition system components, such as the spark plugs, wires, or coil, can cause the engine to stall because they are not providing the spark necessary to ignite the fuel. The engine may also run rough or have a loss of power.
