How Long Do Spark Plugs Last?

Spark plugs come in three basic types:

  • Iridium plugs, which can go 100k+ miles before requiring replacement (available on select Toyota models)
  • Platinum plugs, which can go 50-60k miles before requiring replacement (available on select Toyota models)
  • Copper plugs, which can go about 20k miles

Plug

However, spark plug life isn't just determined by the type of plug. Fuel quality, engine timing, and ignition system health all factor into it. If you just go by mileage interval to determine when your plugs need replaced, you might have a bad set of spark plugs in your vehicle right now.

Basically, the short answer to the question How Long Do Plugs Last?: It depends.

What Is A Spark Plug?

A spark plug is kind of like a cigarette lighter: It ignites a mix of fuel and air with a spark. However, unlike a lighter that uses a flint to create friction and sparks, a spark plug uses thousands of volts of electricity to generate a spark...and can do so hundreds of times per minute.

A spark plug starts to degrade when it can no longer generate a sufficient spark. It can be covered with soot from unburned fuel, contaminated due to bad fuel, damaged from excessive heat, etc. Basically, anytime anything goes wrong in your vehicle's engine, your spark plugs are likely to be affected.

Spark plugs are pretty resilient, which means that they'll continue to function even if they're damaged. However, damaged spark plugs cost you money and should be replaced. A damaged plug will cause your vehicle to burn more gas than it should. A damaged plug will hamper acceleration and performance too, and can eventually lead to engine damage if not corrected.

Changing Spark Plugs

Plugs

On most engines, spark plug replacement is straightforward and affordable. For this reason, we often recommend spark plug replacement as preventative maintenance based on vehicle age or mileage. However, if you have any symptoms of a bad plug:

  • Poor fuel economy
  • Slow acceleration and/or hesitation
  • Weird engine or exhaust sounds, and/or engine stalling or "cutting out" at random times

Order a set of genuine replacement OE spark plugs for your Toyota. Like most things, an early repair (or spark plug replacement) can save a mountain of money later.

Written by Jason Lancaster