A vacuum leak can cause a whistling or hissing sound, especially when the engine is idling. The sound may also be accompanied by a rough idle, stalling, or decreased performance. To find a vacuum leak, inspect all the vacuum hoses and connections for cracks or breaks. You can also use a spray bottle filled with soapy water to spray around the hoses and connections. If you see bubbles forming, there is a leak.
2. Vibration
Vibration at idle can be caused by several different factors, including:
* Engine mounts: The engine mounts are responsible for securing the engine to the frame of the car. If they are worn or damaged, they can cause the engine to vibrate excessively.
* Transmission mount: The transmission mount secures the transmission to the frame of the car. If it is worn or damaged, it can also cause vibration at idle.
* Driveshaft: The driveshaft connects the transmission to the wheels. If it is bent or damaged, it can cause vibration at idle.
* Wheel bearings: The wheel bearings allow the wheels to rotate smoothly. If they are worn or damaged, they can also cause vibration at idle.
To determine the cause of the vibration, you will need to inspect each of these components. You can also take your car to a mechanic to have it diagnosed.
