How Long Do Spark Plugs Last? Real Lifespan and Signs of Wear
When you think about what keeps your car running, spark plugs, small but critical components that ignite the fuel-air mixture in your engine. Also known as ignition plugs, they’re not something you notice—until they fail and your car starts misfiring, struggling to start, or losing power. Most modern spark plugs are designed to last between 60,000 and 100,000 miles, but that’s not a guarantee. Driving habits, engine condition, and even the type of fuel you use can cut that life in half.
It’s not just about mileage. If you do a lot of short trips in cold weather, your engine never fully warms up, which causes carbon to build up on the plugs. That’s called fouling, when deposits coat the electrode and prevent proper sparking. If you’re using cheap fuel or your car has an oil leak, that’s another path to early failure. And don’t assume a new plug lasts forever—some performance engines or modified cars burn through them faster. The engine performance, how efficiently your car converts fuel into motion depends on these tiny parts working perfectly.
You don’t need a diagnostic tool to know when they’re done. If your car hesitates when you press the gas, feels rough at idle, or the check engine light flashes, it’s often the spark plugs. You might also notice your fuel economy dropping—no magic trick, just bad ignition wasting fuel. And if you hear a clicking or popping sound from the engine, that’s not normal. These aren’t just minor annoyances. Worn spark plugs can damage your catalytic converter, which costs far more to replace than a set of plugs.
What’s in the collection below? Real stories from UK drivers who found out the hard way. Posts that break down how to check your own plugs, what different types are best for your car, and whether upgrading to iridium or platinum makes sense—or just wastes money. You’ll see what happens when people ignore the signs, and what actually works when they act early. No fluff. Just what you need to know before your next service or auction run.
