During the past decade, concerns about the negative effects of vehicle emissions on the environment have increased. Every vehicle on the road is required by law to undergo a smog emissions diagnosis to ensure the emitted gases meet state regulations. One of three tests will be implemented on a vehicle to ensure that it meets emission requirements.
The Different Tests for a Smog Check
Depending on the age of the vehicle, a standard smog check will consist of a test that monitors specific gas outputs, tail pipe emissions or computer diagnostics. ASM2, OBD2 and TSI are the three types of smog checks that are used to test vehicles.
ASM2 - Acceleration Simulation Mode 2
The Acceleration Simulation Mode 2 measures exhaust emissions for levels of gases like hydrocarbon, carbon monoxide, and nitrogen oxides. Car movement is simulated using a dynamometer, which replicates traction with a "treadmill-like" device, while a five-gas analyzer tracks emissions.
TSI -Two Speed Idle
The Two Speed Idle emissions test is used to check the smog output on vehicles at high and low speeds. This test measures the tailpipe exhaust emissions while the vehicle maintains certain speeds.
ODB2- On-Board Diagnostics Second Generation
The On-Board Diagnostics Second Generation is a system that triggers the service engine dashboard light whenever an emissions malfunction is recognized. During a smog check the servicemen will tap into the vehicles diagnostic link connector and be able to pinpoint where the malfunction has occurred based on stored information.
Smog Checks are Vehicle Specific
TSI and ASM2 are used for vehicles registered before 1995. OBD2 is used to check emissions by reviewing data taken by the computers in newer vehicles.
What Is Industrial Smog?
Industrial smog is caused by burning coal and other hydrocarbons. Smog is harmful to humans and can lead to acid rain.
What is the Cost of a Smog Check in California?
California law requires that all vehicles (with few exceptions) be inspected and repaired to comply with auto emissions standards to register or...
Can I Test My Car Emissions at Home?
Cars and trucks stuck in traffic can cause smog, which reduces air quality. For this reason, some states and cities require residents...
How to Sell a Car in California Without a Smog Certificate
In California, there are more drivers on the road than in any other state in the nation, which means more smog, and...
What Are the Causes of Smog Test Failure?
State and federal governments have placed limits on harmful gasses emitted by vehicles. An emissions test, also referred to as a smog...