Something else: Check the plugs on a regular basis. They can tell you important information about how well the fuel/air mixture is being maintained, and if there's any problems with it.
They also wear down over time, and NEED replacement. ONLY use the recommended replacement plugs, not some expensive, iridium/platinum plug. Don't use anything made for European vehicles. They don't get along with the Japanese systems in our 4Runners.
They can also tell you that the coils and/or plug wires are encountering any problems, which is critical information for you.

Keep an eye on the brake fluid. The darker it gets, the more water it's absorbed, and the less well it will work. It should be replaced at most every 4-5 years, or when it's much darker than can be seen through. Be careful not to let the master cylinder suck air in during the bleeding process. Keep it full to the FULL line, as you bleed it down.

Check any and all the plastic parts in the engine compartment. Over time, they get brittle, and can disintegrate at a touch. Especially things like the hot water control valve.

Keep an eye on the high-current connectors. The alternator, starter, battery, and so forth. Keep the ground points clean and free of corrosion and contamination.

OK, OK, shutting up now...
Pat☺