Technical Tips

Remember: Always consult your owner's manual.

All About Tune Ups

We often have people request a tune up when their vehicle's engine is running rough.

Most vehicles made since the early 1980s require a "Tune Up" only once every 30,000 miles. Some of today's new cars and trucks don't need a tune up for 60,000 miles!

Actually, there is no such thing as a "tune-up" anymore. It's really preventive maintenance and involves changing the spark plugs, inspecting or replacing the air filter, fuel filter, PCV valve and inspecting engine performance.

Webster's Dictionary defines a tune up as "an adjustment to assure efficient functioning". In the early 1970s when many cars still had point ignition systems, inspecting and adjusting the points and ignition timing every 12,000-15,000 miles was usually necessary to compensate for wear. Making adjustments with the carburetor idle speed and idle mixture was also part of the "tune up". Also every engine back then ran on leaded gasoline, which meant the spark plugs rarely lasted 12,000-15,000 miles before they became fouled with carbon deposits. Because of this, annual "Tune Ups" were established.

With the arrival of electronic ignition systems, the need for the periodic adjustment was eliminated. Once set, the ignition timing will remain unchanged unless something is failing. At this point the engine would usually cease running. The switch to unleaded gasoline stretched the spark plug life to 30,000 miles, so the annual "tune up" is a thing of the past.

Today, virtually everything from the idle speed to the ignition timing is computer controlled. Since there is nothing left to "tune" in the traditional sense, what is normally required for proper maintenance is to change the spark plugs, air & fuel filters, and inspect other wear items periodically.

Back then, having a "tune up" performed usually restored engine performance and was often credited for being a "cure- all" for what ailed your engine. This is not the case today. If your engine is running rough, proper diagnostics by a skilled and certified technician is required to find what is causing the rough running condition.

What Is a Tune Up?

The term "tune-up" was coined back when Henry Ford was working on his first prototype for the automobile. The first ignition system was very simple; one ignition coil for one spark plug, so if there were four spark plugs, there would be four ignition coils. These ignition coils needed to be adjusted to provide the same spark intensity for better idle and acceleration. As these coils worked, they made a buzzing sound. So when the ignition coils were adjusted properly, they all buzzed the same tune...thus, they were in tune and that is how the term "tune up" was coined. This term stuck and was associated with the replacement of the spark plugs and any performance or rough idle problem that could be associated to engine operation. Once the distributor was developed, the term had no meaning as to how an engine performed. The consumer, however, still automatically associates poor running quality with the need to be in tune.

Today's automobiles do not require tune ups. Automobile manufacturers have set forth, in there recommended maintenance schedules, intervals for replacing spark plugs, PCV valves, Fuel filters etc., while recommending that other items related to engine operation be inspected for proper operation and/or adjustment, such as ignition timing, idle speed and other emission control related devices. When and only when the maintenance has been performed would a performance problem be addressed to correct any given set of problems. If an operating or performance problem is still present after the maintenance has been performed, an engine analysis would be required. Therefore, the term "tune up" indicates the need for routine maintenance and should not be associated with poor performance. If your vehicle experiences any operation or performance problems between maintenance intervals, that specific problem should be addressed by performing an engine analysis to isolate that particular problem.