Drive Clean

The Ontario Drive Clean emissions test can only be performed at an accredited Drive Clean facility by a certified emissions inspector.

Pre-test Check

Before the tail-pipe emissions test can be performed the inspector will perform a visual inspection to check for the presence of a catalytic converter(s) and a gas cap(s) and, will check the condition of the fuel filler pipe. If any of these components are missing, they must be replaced and, any defects must be corrected before the tail-pipe emissions test can proceed. If your vehicle has a problem that would prevent it from being tested safely, or if there is visible smoke being emitted from the tailpipe, it will not be tested until it has been repaired. Such problems could lead to injury, and/or malfunctioning of the test equipment.

If the Malfunction Indicator Light (MIL), also known as the "Check Engine" light, on the dashboard remains illuminated in 1998 and newer model year vehicles, the owners will be advised that it may indicate a malfunction of the vehicle emissions system.

Emissions Test

Ontario's Drive Clean program uses an Accelerated Simulation Mode (ASM) emissions test as its primary test method. This test is conducted on a dynamometer, to simulate actual driving conditions. A probe is inserted into the tailpipe which is connected to a computer that measures the tailpipe emission concentrations of nitrogen oxides (NOx), hydrocarbons (HC) and carbon monoxide (CO). The vehicle emissions are also measured when the vehicle is at idle, in what is called a "curb idle" test. The idle portion of the test measures HC and CO.

Some vehicles, such as those with full-time all-wheel drive, cannot be tested on a dynamometer. These vehicles receive a two-speed idle test, where emissions of CO and HC are measured at curb idle and 2500 revolutions per minute (RPM).

The test results will then be compared to the emissions standards for the vehicle make and model year by the Drive Clean system which will then be presented by the inspector to the vehicle owner in the form of a pass or fail report.