Removing black streaks from a car can be done with a few different methods, depending on the source of the streaks.

Here are some steps you can follow:

1. Wash the Area: Start by washing the affected area with car soap and water to remove any loose dirt and debris.

2. Use a Clay Bar: If the streaks persist, try using a clay bar with a lubricant. This can help lift off any contaminants bonded to the paint.

3. Apply a Detailing Spray: For light streaks, a quick detailer or spray wax can often do the trick. Spray it on and wipe with a microfiber cloth.

4. Use a Streak Remover or Cleaner Wax: If the streaks are more stubborn, apply a cleaner wax or a specialized streak remover. Follow the product instructions and buff the area gently.

5. Baking Soda Paste: For tough streaks, mix baking soda with water to form a paste. Apply it to the streaks with a soft cloth and gently rub. Rinse thoroughly afterward.

6. Polish: If the streaks are still visible, consider using a polishing compound with a foam or microfiber applicator. Be sure to follow up with a wax or sealant afterward.

7. Professional Help: If all else fails, a professional detailer may be able to remove the streaks without damaging the paint.

Always test any product or method on an inconspicuous area first to avoid any potential damage to the paint.