Old spark plugs are not worth much, but you have a few good options: keep a decent one as an emergency spare, scrap the metal, repurpose them for crafts, or just toss the dead ones, since they are small. They cannot go in curbside recycling because they mix metal and ceramic, so do not put them in the recycling bin.
Most people end up with a handful after a tune-up. Here is what to do with them.
Should You Keep Any?
If a removed plug still looks good (light tan tip, no cracks or heavy buildup), clean it, check the gap, and keep it as an emergency backup in your glove box or toolbox. A working spare plug has gotten more than one engine home. Toss any that are oil-fouled, cracked, or worn down.
Scrap the Metal
Spark plugs are mostly steel with a bit of copper and a precious-metal tip (often platinum or iridium on newer ones). A scrap yard will take a bag of them with your other metal. You will not get rich, but it keeps them out of the landfill and adds to a scrap haul.
Repurpose Them
- Turn them into keychains, magnets, or small ornaments
- Use them in industrial-style art, models, or dioramas
- Keep a clean one as a handy gap-gauge reference
How to Dispose of Them
If you cannot scrap or reuse them, old spark plugs can go in the regular trash, since they are small and not hazardous. Just keep them out of the recycling bin, where the mixed materials cause problems. If you are clearing out the garage, see our guides on old car parts and the declutter and recycle guide.
Frequently Asked Questions
Are old spark plugs worth anything?
Not much. They have a small amount of scrap metal value, including a precious-metal tip on newer ones, but no real resale value once used.
Can you recycle spark plugs?
Not in curbside recycling, because they mix metal and ceramic. A scrap metal yard will take them, which is the better option.
Can you reuse a spark plug?
Yes, if it still looks good. Clean it, check the gap, and keep it as an emergency spare. Replace any that are fouled, cracked, or worn.
How do you dispose of old spark plugs?
Scrap the metal if you can, or put them in the regular trash since they are small. Keep them out of the recycling bin.