If your gas-powered vehicle’s acceleration has gone from “zoom, zoom” to “putt, putt,” there’s probably a spark plug problem.
Poor fuel economy is another indication the plugs or spark plug wires likely need replacing. Although modern spark plugs last considerably longer than those produced 30 years ago, they don’t last forever and need to be replaced at regular intervals. It’s best to check the owner’s manual.
Find out what spark plugs do, the types you can purchase, and what signs to look for that signal when they need to be replaced.