What type of inspection is performed?
Gasoline-powered vehicles:There are three types of tests: two-speed idle test, acceleration simulation mode test and an on-board diagnostic system test. 1980 and older model year vehicles, and all vehicles with a manufacturer’s designated gross vehicle weight rating of 8,501 to 10,000 pounds, receive a two-speed idle test. This test measures hydrocarbons and carbon monoxide at 2,500 rpm and curb idle. Most 1981 and newer vehicles with a gross vehicle weight rating up to 8,500 pounds receive an acceleration simulation (ASM) mode test. The ASM test is performed on a dynamometer (also known as a treadmill) which allows the inspector to run the vehicle at only 15 mph and 25 mph. This type of test is performed to measure nitric oxide, as well as hydrocarbons and carbon monoxide. Some vehicles may not be able to receive the dynamometer test due to mechanical features such as all-wheel drive, full-time four-wheel drive, or traction control that cannot be turned off. These vehicles will be tes
