1. Throttle Position Sensor (TPS): The TPS tells the engine control module (ECM) the position of the throttle valve. If the TPS is defective, it can send incorrect signals to the ECM, causing the engine to stall. Test the TPS with a multimeter to ensure it is functioning properly.
2. Idle Air Control (IAC) Valve: The IAC valve controls the amount of air that bypasses the throttle valve when the engine is idling. If the IAC valve is dirty or faulty, it can cause the engine to stall. Clean the IAC valve and check its operation to ensure it is functioning properly.
3. MAF Sensor: The Mass Air Flow (MAF) sensor measures the amount of air entering the engine. If the MAF sensor is dirty or defective, it can provide incorrect readings to the ECM, causing the engine to stall. Clean the MAF sensor and check its operation to ensure it is functioning properly.
4. Vacuum Leaks: Vacuum leaks can cause the engine to run lean and stall. Inspect the vacuum lines for cracks or breaks and make sure they are properly connected.
5. Fuel Pressure Regulator (FPR): The FPR controls the fuel pressure in the fuel system. If the FPR is faulty, it can cause the fuel pressure to be too low or too high, which can cause the engine to stall. Test the FPR to ensure it is functioning properly.
6. Oxygen Sensor: The oxygen sensor monitors the amount of oxygen in the exhaust gas and provides feedback to the ECM to adjust the air-fuel mixture. If the oxygen sensor is defective, it can provide incorrect readings to the ECM, causing the engine to stall. Test the oxygen sensor to ensure it is functioning properly.
7. ECM: The ECM is the computer that controls the engine. If the ECM is defective, it can cause the engine to stall. Have the ECM diagnosed by a qualified mechanic to ensure it is functioning properly.
If you have replaced the injectors and fuel pump and the engine is still stalling, it is recommended to have the vehicle diagnosed by a qualified mechanic to identify the root cause of the problem.
