What to Do When Car Key Gets Rusty?

[BryceDella]

First, use a clean paper towel to wipe it clean. If there are only sporadic rust spots on the surface, you can soak the key in vinegar to loosen the rust, then wipe it with a hemp cloth. Iron sandpaper is primarily used to remove rust, providing a good polishing effect, making it smoother without affecting the key's shape.

[Roman]

The key to my old car rusted last year, and it took several attempts to fix it. First, gently sand the rust off the surface with fine sandpaper, being careful not to damage the chip. Then, clean it with a cotton swab dipped in white vinegar, and apply some sewing machine oil to prevent further rust. If the keyhole is sticky, a little WD-40 works best. If the transponder key is completely rusted through, you’ll need to get a new one—last time it cost me over 300 yuan. Now I’ve developed a habit: after using the key on rainy days, I dry it with a hairdryer and store it in a waterproof key pouch, which saves a lot of hassle. Car owners living by the sea need to be extra careful, as saltwater is particularly corrosive to metal keys.

[NoraMarie]

After my last workout, I found my car key got rusty from sweat, which was really annoying. I tried soaking the old key in cola and it worked okay, but I had to dry it immediately. Later, I bought a special rust remover for 10 yuan a bottle, which lasts a long time. Now I keep my spare key in a moisture-proof box and put a silicone cover on the main key. A reminder: never use strong acid to remove rust—my neighbor Lao Wang’s key got completely corroded last time. Getting a smart key replaced at a 4S shop costs over a thousand yuan, while a locksmith shop charges around 300 yuan, but make sure to choose a licensed one.

[MaxLee]

Veteran car owners share a folk remedy: Insert a rusty key into a potato and twist it a few times—the starch can absorb the rust. Daily maintenance is simple: Avoid storing keys with coins, as metal friction accelerates rusting. In humid coastal areas, it's advisable to check the key's condition monthly. If the rust is severe, don't force it—you risk breaking the key in the lock, which is more troublesome. When getting a new key, remember to bring your vehicle registration—modern keys require anti-theft chip matching, a technical task best left to professionals.