Following is a compilation of vacuum diagrams for most of the engine and emissions package combinations covered by this manual. Because vacuum circuits will vary based on various engine and vehicle options, always refer first to the vehicle emission control information label, if present. Should the label be missing, or should the vehicle be equipped with a different engine than the car's original equipment, refer to the following diagrams for the same or similar configuration.
If you wish to obtain a replacement emissions label, most manufacturers offer them for purchase. These labels can usually be ordered from a local dealer, though you will need to provide them with various serial number or calibration information.