In order to extract the best performance and economy from your engine it is essential that it be properly tuned at regular intervals. Although computerized engine controls and more durable components have reduced ignition maintenance, a regular tune-up will keep your Honda's engine running smoothly and will prevent the annoying minor breakdowns and poor performance associated with an un-tuned engine.
Federal law now requires that manufacturers certify that their vehicle's spark plugs will meet emission rules for 30,000 miles (48,300 km). The maintenance schedules reflect this, showing a mandatory replacement at this mileage. This is a minimum specification; for many vehicles, 30,000 miles (48,300 km) is too long. Plan on at least checking spark plugs and other ignition components at least once per year. Check them anytime a deterioration of engine performance is noted. Replaceable tune-up components are relatively inexpensive compared to the inconveniences of a poorly running vehicle or one that will not start.
This inspection interval should be halved if the car is operated under severe conditions, such as trailer towing, prolonged idling, continual stop and start driving, or if starting or running problems are noticed. It is assumed that the routine maintenance described in Routine Maintenance has been kept up, as this will have a profound effect on the results of a tune-up. All of the applicable steps of a tune-up should be followed in order, as the result is a cumulative one.
If the specifications on the tune-up or emission label in the engine compartment of your Honda disagree with the tune-up specifications chart in this section, the figures on the sticker must be used. The sticker often reflects changes made during the production run.