Here's why:
* Severe damage: The loud noise indicates the compressor is struggling and likely damaged. Continuing to run it could lead to complete compressor failure, potentially causing further damage to the AC system (e.g., seized components, refrigerant leaks). Repairing this damage will be far more expensive than just replacing the compressor.
* Safety hazard: A failing compressor can seize, potentially causing a belt to break. This could lead to loss of power steering and alternator function, making the car unsafe to drive.
* Refrigerant loss: The cycling sound might indicate refrigerant is escaping. Refrigerant is harmful to the environment and can also damage the compressor further.
In short, while you might be able to limp it along for a short distance to a safe location, it's best to have the compressor diagnosed and repaired or replaced as soon as possible to avoid more serious and expensive problems. Driving it long distances with a failing compressor is risky.
