Ventilation is part of the acceptable indoor air quality and thermal comfort problem. Carbon monoxide (CO) is a highly toxic gas that's emitted from cars in vehicular spaces. A new strategy of ventilation called periodic supply exhaust strategy is used. The term PRESEV stands for Periodic Reversible Supply Exhaust Ventilation strategy. The main advantage of PRESEV strategy is reducing air flow rate requirement and also achieve averaged CO ppm rise according to standards. With the PRESEV strategy a ventilation flow rate 27% of that required by conventional piston or mixed ventilation strategies could achieve the same maximum hourly averaged local CO ppm rise. This paper aims at proving the effectiveness of the PRESEV ventilation strategy to the conventional ventilation strategy. A 27 % saving in fresh air flow rate was achieved using PRESEV strategy also the strategy satisfies AS 1668.2.Half hourly PRESEV strategy has proved that it gives results equal to Hourly PRESEV strategy and it efficiently satisfies AS 1668.2.