My handbook states change spark plugs every 100k miles. Isn't that an extreme amount of miles for spark plugs.

 

Nope.

 

Not at all. Although your mileage may vary, the plugs (meaning the material) they use, and the technology in the car behind them, means they will indeed last that long.

I changed mine at 97K or thereabouts, because she was acting a little unhappy, but you might get 120 before it's a problem. A few have.

 

That is impressive, could fouled plugs cause an unsteady idle?

 

My wife's '02 escape had original plugs at 130k. I just replaced them... as preventative maintenance. They weren't even acting up yet.

 

That, and hesitations.. it'll be real obvious that it's ticked off about 'em. Seems like it also felt like a slipping clutch, sorta, on take offs too. It just acts... strange.

Swap the plugs, and tada, it's a brand new CAR!!!

/game show announcer voice.