See Figure 1
In order to extract the full measure of performance and economy from your engine, it is essential that it be properly maintained and tuned. A tuned engine is extremely important to the control of tailpipe emissions.
Because of the more durable components and computer controlled systems on modern vehicles, the annual tune-up of yesterday is gone. The most important thing you may do for your vehicle, to optimize performance and help prevent vehicle breakdown, is to follow the Maintenance Intervals Chart in General Information & Maintenance . The next most important way to assure your vehicle is tuned and running properly is to thoroughly familiarize yourself with the ignition system and other engine control systems. Understanding the ignition will help you to detect subtle changes in the system which might require repair or maintenance.
A vehicle should be thoroughly inspected and tuned at least every 30,000 miles, though as you can tell from General Information & Maintenance of this guide, there are many components which need more frequent attention. Also, this time frame should be halved if the vehicle is operated under severe conditions such as trailer towing, prolonged idling, start-and-stop driving, or if starting or running problems are noticed.
As stated earlier, it is helpful to understand the system and know how it should be operating so that you can detect symptoms before problems develop. Your car's idle speed is noted in the Tune-Up Specification Chart, but can also be found on the emission information label in the engine compartment. If your Spectrum or Storm is equipped with a tachometer, you can easily check for the proper idle speed whenever you are in the car.
The emission information label often reflects changes made during the model year. If any of the specifications on the label disagree with the Tune-Up Specification chart or text in this Section, use the figures on the label.