What’s Included in a Tuneup?

A car tuneup is an outdated service consisting of replacing parts to bring the ignition and fuel systems up to spec for maximum engine performance and efficiency. A traditional tuneup hasn’t been available or necessary for years. Today’s remaining tuneup services include new spark plugs and cabin air filter replacement. Both are part of your vehicle’s maintenance schedule just as much as checking tire pressure or getting an oil change are — and today’s “tuneup” services are likely to be more like checkups for your car.

Spark plugs, for example, are typically replaced every 100,000 miles. And the federal EPA and Department of Energy say that replacing a clogged air filter will not improve gas mileage but can improve acceleration by roughly 6 to 11 percent. The agencies do not say what benefit can be derived from fresh spark plugs, but computers that control today’s engines adjust the air-fuel mixture and spark timing to compensate for wear, such as when the electrodes on spark plugs are worn down.

Even so, some car owners still dutifully take their vehicle in periodically to have it “tuned up.” Instead, what actually happens is that service technicians will inspect and perhaps test the fuel, ignition and emissions systems to look for faulty vacuum hoses, oxygen sensors and various other parts that can hurt the car’s performance. The federal government, for example, says a bad oxygen sensor can give engine computers false readings and reduce fuel economy by as much as 40 percent.

Don’t Ask for a Tuneup, Just Follow Your Car’s Maintenance Schedule

Having your vehicle serviced and inspected periodically is a good way to extend its life and keep it operating efficiently. (Here are some signs your car needs to be checked by a mechanic.) However, walking into a repair facility and asking for a tuneup is a bad idea because it indicates you’re still living in a previous century with no knowledge of what your car actually needs and have extra money to spend. Some in the auto repair business will take advantage of those opportunities.

Look in the owner’s manual for your vehicle (or separate maintenance schedule) to find what the manufacturer recommends, and see if you can even find the word “tuneup.” (Finding it with a hyphen counts; don’t worry, we’ll wait.) For example, we looked at the maintenance guide for the Ford Fiesta that also applies to other Ford vehicles. The first mention of anything related to a traditional tuneup was to replace the engine air filter every 30,000 miles. The only other related item was to replace the spark plugs every 100,000 miles.