Spark plugs are one of the few parts that I tell people that if they suspect they’re bad, just go ahead and replace them. They’re not expensive, easy to replace*, and if you don’t know specifically the last time they were replaced - you’re better off starting to keep track with a new set.

• • some manufacturers make it a pain

That center electrode looks pretty worn down to me. But my eyes are not a feeler gauge. Check with feelers to be sure.

How often does your owner’s manual say to swap plugs?