Cars built in the last 25 years are mostly self-tuning thanks to computers. So when someone says "tune-up" today, they're really asking for scheduled maintenance — replacing the wear items that the engine computer can't fix on its own. Here's the modern checklist.
Spark plugs
Most modern engines run iridium plugs that last 100,000 miles. But platinum and copper plugs (older or budget cars) need replacement every 30,000-60,000. Symptoms of bad plugs: rough idle, hesitation under load, misfire codes (P0300-P0308), worse fuel economy. Replacing plugs in a modern engine often means removing intake manifolds — labor varies wildly by vehicle.
Air filter
Engine air filter — replace every 15,000-30,000 miles or sooner if you live near construction or drive dirt roads. A choked filter costs you measurable horsepower and fuel economy.
Cabin air filter — totally separate. Replace every 15,000 miles. Cleans the air YOU breathe and helps your A/C and heater work properly. Often skipped because it's hidden behind the glove box.
Fuel filter (if applicable)
Most modern cars have a lifetime fuel filter inside the gas tank. Some still have an external one to replace at 50,000-90,000 miles. Diesels usually need them more often.
PCV valve
Tiny crankcase-ventilation valve. When it fails you get oil leaks, oil burning, rough idle. $20 part, often skipped — but should be checked at every tune-up.
Coolant flush
Coolant breaks down chemically. Replace every 5 years or 60,000 miles. Old coolant becomes acidic and starts eating the heater core, water pump, and head gasket from the inside.
Transmission fluid
Manufacturer schedules vary wildly — 30k for some, 100k for others, "lifetime" (sometimes accurate, sometimes a marketing lie) for many. Burnt or dirty transmission fluid kills automatic transmissions.
Brake fluid
Every 3 years. Brake fluid is hygroscopic — it absorbs water from the air, which lowers its boiling point and rusts internal brake parts.
Belts & hoses
Visual check at every service. Cracks, glazing, soft spots in hoses = replace before they fail. A snapped belt or burst hose can leave you stranded — a 30-second inspection prevents it.
Battery test
Every visit. A weak battery still starts the car for a while before it doesn't. Loadtest takes 60 seconds and tells you if you'll be calling AAA next month.
What we do at BTW
Every oil change includes a 21-point inspection that covers all the items above (except spark plug replacement, which is its own job). If something's coming due, we tell you. If it's fine, we say so. No upselling. Call (916) 627-1998 to schedule.