Do a search for the phrase “car hacks” online and you’ll be flooded by cheap fixes for all sorts of automotive afflictions. But can you really use toothpaste to clean your headlights? And does nail polish actually protect against rust? We asked our resident car-care expert, Ryan Peterson, manager, automotive services, at CAA South Central Ontario, to weigh in.

The hack: Touch up paint chips with nail polish

The logic: The polish will protect exposed metal, keeping water and oxygen at bay and preventing rust. Peterson’s take: The hack will work, but only for a little while. Wind, rain and snow will quickly eat away at the polish, exposing the metal underneath. It’s far better to spend a few dollars on proper touch-up paint.

The hack: De-ice a frozen door lock with hand sanitizer

The logic: The alcohol in hand sanitizer will melt the ice wedged in the lock, freeing it up. Peterson’s take: If the ice is near the surface, this hack will work. But hand sanitizer can’t reach deep within a lock, which is where ice often forms. A better solution: if your locks are prone to freezing, spray them with powdered graphite—a type of grease—before the cold weather hits.

The hack: Use a plunger to smooth out dents

The logic: By harnessing the power of suction, you can yank out minor divots in your car’s bodywork. Peterson’s take: This really does work. While the result won’t be as pretty as what you’ll get by going to a body shop, “if you get an airtight seal and you have a good plunger, you can actually pull [a dent] out,” he says.

The hack: Restore cloudy headlights by buffing them with toothpaste

The logic: The toothpaste will eat away the grime on your headlights, which are made from plastic, and leave them looking like new. Peterson’s take: This is a temporary fix. After a few months, they’ll be back to their cloudy old selves. For lasting clarity, bring your car to a body shop, where they’ll use a special polisher and rubbing compound to shave off a thin layer of your headlights. That will expose the clear, clean plastic below.

The hack: Slow a windshield crack by dabbing on some nail polish

The logic: The bonding power of nail polish will hold the crack together and help you avoid an expensive trip to the body shop. Peterson’s take: No. Cracks get worse when one side of your windshield is blasted with hot air and the other is exposed to cold, wintry air. That causes the glass to heave in a powerful reaction. “I’ve never seen nail polish strong enough to stop [that],” he says.

The hack: Use hair conditioner to shine your car

The logic: If you’re short on wax, conditioner with lanolin will give your car a rich, lustrous glow. Peterson’s take: Avoid doing this. Conditioner only lasts for a day or two in actual hair. On a vehicle, it will wash away in a drizzle, and any shine you see will just be grease. Instead, opt for car wax, which is cheaper than conditioner.

While Internet hacks might work in a pinch, they’re no substitute for professional help.  If something goes wrong with your car, consult your local mechanic or reach out to CAA’s Consumer and Technical Services, which offers Members free car-care advice. Call them at 1‑866‑464‑6448 or connect via email at cats@caasco.ca.