In order to extract the best performance and economy from your engine it is essential that it be properly tuned at regular intervals. A regular tune-up will keep your Toyota's engine running smoothly and will prevent the annoying minor breakdowns and poor performance associated with an untuned engine.
All Toyota Celicas had a conventional breaker point ignition system through 1974. In 1975 Toyota switched to a transistorized ignition system. This system is much like the previous system with one basic difference; instead of the breaker points switching the primary current to the coil on and off, they trigger a transistor which does it for them. In 1977, Celica GT's sold in California came equipped with a fully transistorized electronic ignition system. In 1978, this system became standard on all models.
A complete tune-up should be performed every 15,000 miles (24,100 km) or twelve months, whichever comes first. This 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 General Information & Maintenance has been kept up, as this will have a decided 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 sticker in the engine compartment of your Toyota 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.