Passenger cars and trucks that have to be emissions tested may or may not pass if the service engine light is on. If your vehicle is 1996 or newer, it will fail. It will fail regardless of why the light is on. The Department of Environmental Quality will not pass your vehicle through emissions until the check engine light is off. The light has to be off and the monitors have to have run their tests before they will pass the vehicle.
If the vehicle is a 1995 or older, it does not matter if the light is on. The vehicle will have to be within specifications for both HC and CO gases. If the vehicle is within the given specifications, they should pass the vehicle as long as the gas cap and other emissions control devised have not been tampered with.
AASTRO Transmissions and Auto Repair can take care of all of your cars/trucks needs. 4443 W. Ina Road Tucson, AZ 85741 520-744-0655, Call for your appointment today!