my car cranks but doesn't start. I unplug the fuel pump then it starts. I've already changed the fuel pump and also, It's not because of the anti-theft.
You're starting it after unplugging the fuel pump? It won't stay running very long before your engine stalls out again! You may have a bad fuel pressure regulator that is dumping fuel into the intake causing the engine to flood when you first try and start the car.
Depending on the vehicle and engine the fuel regulator will have a vacuum line on some designs. Disconnect the line and turn they key on to see if fuel comes out. If it does then replace regulator. If the regulator is on the spider inside of the intake then leak the fuel pump connected to it. Then try holding the gas pedal to floor and see if it starts and stays running. You may have a bad spider and regulator in this case.
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