Dreams about losing a car can symbolize feelings of loss of control or direction in your life. The car often represents your journey or how you navigate through life. Parking your car at a mechanic's garage could signify a need for repair or assistance in some aspect of your life.

The inability to find your car may reflect feelings of frustration or helplessness regarding a situation you’re currently facing. Asking the mechanics for help and getting no answers could indicate feelings of being unsupported or misunderstood by those around you.

The act of wanting to arrest the mechanic suggests a desire for accountability or justice in a situation where you feel wronged or taken advantage of. The boss being the perpetrator could symbolize a larger issue of authority or control that you feel is not acting in your best interest.

Overall, this dream might be urging you to confront feelings of powerlessness and seek clarity in areas where you feel lost or unsupported. It could be beneficial to reflect on situations in your waking life where you feel the need for assistance or where accountability is lacking. Consider addressing these issues directly or seeking support from trusted individuals.