My battery died after changing it the engine idles very rough on my 2004 Kia Amanti v-6?

1. Loose or Damaged Battery Cables: Ensure the battery cables are securely connected and not damaged. Loose or damaged cables can cause poor electrical connections, affecting engine performance.
2. Faulty Alternator: The alternator is responsible for charging the battery and supplying electrical power to the engine. A faulty alternator may not be providing enough power, resulting in rough idling.
3. Idle Air Control (IAC) Valve Issue: The IAC valve controls the amount of air that enters the engine at idle. A malfunctioning IAC valve can cause the engine to idle erratically.
4. Mass Air Flow (MAF) Sensor: The MAF sensor measures the amount of air entering the engine. If the MAF sensor is dirty or faulty, it can provide incorrect data to the engine control unit (ECU), affecting the air-fuel mixture and causing rough idling.
5. Vacuum Leaks: Check for any vacuum leaks in the engine. Vacuum leaks can cause unmetered air to enter the engine, disrupting the air-fuel ratio and leading to rough idling.
6. Spark Plugs and Ignition System: Worn-out spark plugs or issues with the ignition system, such as faulty spark plug wires or coils, can cause misfires and rough idling.

If you are unable to identify the cause of the rough idling, it is recommended that you take your vehicle to a qualified mechanic for further diagnosis and repair.