# ENGINE PERFORMANCE AND TUNE-UP

## TUNE-UP PROCEDURES

In order to extract the full measure of performance and economy from your engine it is essential that it is properly tuned at regular intervals. A regular tune-up will keep your Datsun/Nissan engine running smoothly and will prevent the annoying breakdowns and poor performance often associated with an unmaintained engine.

On all models covered in this manual, the spark plug replacement interval is 30,000 miles or 24 months.

This interval should be halved if the car is operated under severe conditions such as trailer towing, prolonged idling, start-and-stop driving, or if starting or running problems are noticed. It is assumed that the routine maintenance described in Section 1 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 underhood tune-up sticker in the engine compartment of your car 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.

A tune-up should consist of replacing the spark plugs and checking spark plug wires, distributor cap and rotor. If necessary replace the air filter, gas and all other emission filters. All vacuum lines and hoses should also be checked and all necessary engine adjustments should also be made at this time. It might be noted that the tune-up is a good time to take a look around the engine compartment for problems in the making, such as oil and fuel leaks, deteriorating radiator or heater hoses, loose and/or frayed fan belts and etc.

GASOLINE ENGINE TUNE-UP SPECIFICATIONS