NO TUNE-UP FOR 100,000 MILES! Sounds incredible? But thats what some carmakers are claiming. Has new technology rendered the tune-up unnecessary? The truth is, the term tune-up as weve known it has become obsolete. The term dates back to the days when engines were cranked by hand and the spark to fire the spark plugs was generated in a fancy-looking, varnished wooden box.
The ignition box often need to be adjusted to the right pitch, hence the tune-up. In those days before electronic engine controls and onboard computers, the basic engine timing, distributor point gap, fast idle and automatic choke often needed to be adjusted, usually at the same time the spark plugs needed replacing. A tune-up meant changing the plugs, points and condenser and making any necessary adjustments for the engine to run at peak power and efficiency. Modern computer controlled and fuel injected engines dont need those adjustments. The computer does all the adjusting. When it comes to the 100,000 mile tune-up, carmakers mean that under normal driving conditions, they anticipate that the spark plugs on certain engine models will not need to be changed for 100,000 miles.
Todays sophisticated engines are held to higher standards of efficiency. To meet ever-stricter emission controls, they need to be checked periodically to ensure they are operating efficiently. A simple vacuum leak or dirty air filter could dramatically decrease fuel consumption and exhaust emissions. A lump of carbon or small quantity of oil could foul a spark plug. Left unrepaired until the recommended tune-up interval, increased fuel consumption costs and potential damage to expensive parts, like the oxygen sensor or catalytic converter, far exceed any money saved by assuming nothing need to be done until a tune-up is recommended. Remember, potentially longer-lasting spark plugs dont guarantee an engine will run efficiently without any attention
Generally, aside from spark plugs, the need for servicing remains the same. Filters should be changed regularly and at about 50,000 miles, ignition wires may need replacing. The distributor cap and rotor may show some wear and fuel injectors may get dirty. To help avoid unnecessary tune-ups, have your engine analyzed annually.