* California and other states with stricter emissions standards: A 1993 Silverado sold in California or a similar state *likely* had a smog pump (also called an air injection pump). These pumps injected air into the exhaust system to help burn off pollutants.
* Other states with less stringent emissions standards: A 1993 Silverado sold in a state with less strict regulations might *not* have had a smog pump.
To know for certain if *your* specific 1993 Chevy Silverado needs a smog pump, you should:
1. Check your vehicle's emission sticker: This sticker, usually located under the hood, will list the emissions equipment installed on the vehicle.
2. Check your owner's manual: The owner's manual might specify the emissions equipment.
3. Check your state's emissions requirements: Your state's Department of Motor Vehicles (DMV) website will have information on emissions requirements for vehicles of that year and model.
If the smog pump is missing and your vehicle is registered in a state requiring it, you will likely fail an emissions test.
