What would cause your engine to die when it decelerates quickly but idle just fine starts or slowly not fuel filter?

- Vacuum leaks: A vacuum leak can cause the engine to run lean, which can lead to stalling when the throttle is closed. Check for any loose or cracked hoses in the vacuum system.

- Idle air control valve: The idle air control valve (IAC) regulates the amount of air that bypasses the throttle body at idle. If the IAC is faulty, it can cause the engine to stall when the throttle is closed.

- Throttle position sensor: The throttle position sensor (TPS) tells the engine control unit (ECU) how far the throttle is open. If the TPS is faulty, it can send an incorrect signal to the ECU, which can cause the engine to stall when the throttle is closed.

- Fuel pressure: Low fuel pressure can cause the engine to stall when the throttle is closed. Check the fuel pressure to ensure it is within the manufacturer's specifications.

- Mass air flow sensor: The mass air flow sensor (MAF) measures the amount of air entering the engine. If the MAF is faulty, it can send an incorrect signal to the ECU, which can cause the engine to stall when the throttle is closed.