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 Celica's engine running smoothly and will prevent the annoying minor breakdowns and poor performance associated with an untuned engine.
A complete tune-up should be performed every 15,000 miles (24,000 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 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.