1. Engine mounts: Worn or damaged engine mounts can cause the engine to vibrate excessively, especially when the AC compressor is engaged. Inspect the engine mounts for signs of wear or damage, and replace them if necessary.
2. AC compressor: A faulty or failing AC compressor can also cause the car to vibrate. Check the AC compressor for any signs of damage or leaks, and have it repaired or replaced if necessary.
3. Serpentine belt: The serpentine belt drives the AC compressor, and a worn or damaged belt can cause the engine to vibrate. Inspect the serpentine belt for signs of wear or damage, and replace it if necessary.
4. Idler pulley: The idler pulley is a component of the serpentine belt system that helps to keep the belt tensioned. A worn or damaged idler pulley can cause the belt to vibrate, which can in turn cause the engine to vibrate. Inspect the idler pulley for signs of wear or damage, and replace it if necessary.
5. Vacuum leak: A vacuum leak can also cause the engine to vibrate. Check for any loose or disconnected vacuum hoses, and repair or replace them if necessary.
