This investigation pertains to the emission levels of carbon monoxide, carbon dioxide and hydrocarbons from the vehicles that are plying in Madurai city. Hundred vehicles each from petrol driven vehicles such as mopeds, motorcycles (two stroke), motorcycles (four stroke), auto rickshaws (three wheelers) and cars and diesel fueled vehicles such as jeeps, vans, buses (inter city), buses (intra city) and trucks are tested and the emission characteristics are summarized.