The traditional meaning of tune-up is replacing spark plugs and the air filter periodically. The EPA and Department of Energy reported that changing a clogged air filter won’t improve gas mileage but will improve acceleration to 6 to 11 percent. The organizations didn’t say anything about the benefits of replacing spark plugs, but today’s computerized car engines can adjust the air-fuel mixture and spark timings to compensate wear.
However, some owners still take their car to the repair shops for a periodic tune up – A mechanic checks the fuel, ignition and emissions system for worn hoses, damaged oxygen sensors, and other components that can affect performance.
Periodic inspection and maintenance is a better way to prolong vehicle’s life and keep its performance. But, driving into a repair a shop and asking for a tune-up is a backdated idea because you are still living in the past century and spending extra money. And many shops will take benefit of those opportunities.
Check your car’s owner’s manual and know what your manufacturer recommends to do, and check if you can find anything about tune-up. For example, I’ve checked the owner’s manual of Ford Fiesta where the first traditional tune-up is replacing the engine air filter every 30,000 miles. The second and last thing was replacing the spark plugs every 100,000 miles.