The number of vehicle (V) in the country is increasing and the traffic flow (TF) increases accordingly in cities as well as on two-lane and multi-lane highways thus the necessity of information on various TF and V parameters becomes topical. Very important parameter of the TF used by traffic organisation and management specialists as well as road construction specialists is TF intensity – the number of V passing by in a particular time unite. This TF parameter is recorded by using automatic device that receives information from the V sensors that might be placed on the road in various ways. The researches done related to the time interval split between V in changing conditions provide credibility of qualitative and quantitative evaluation of TF intensity automatic, uninterrupted control data at various control zones on both two-lane and multi-lane highways. The work analyses the error of V automatic control (recording) caused by situations when two or more vehicles simultaneously cross one control zone that is placed on a multi-lane highway.