A vinegar smell in your car is likely caused by either mold or mildew or a problem with your car’s air conditioner.
If mold or mildew is the cause of the smell:
Use a disinfectant spray designed to fight mold or mildew, or
Create your own disinfectant using one part vinegar, three parts water, and some lemon juice to balance out the vinegar smell.
To use either spray: Turn your AC on full blast, then apply the spray to all vents, including the re-circulation vent, and the AC intake lines.
If the vinegar smell is caused by a problem with your air conditioner: You should take your car to a mechanic to have it fixed. The mechanic can help pinpoint the cause of the odor and will be able to fix the problem if you’re unsure how to do it, or you aren’t confident in doing it yourself.