This paper reports on experiences concerning the deployment of gas sensors on an autonomous mobile robot. It particularly addresses the suitability of the developed system to localize a distant odour source. First experiments were undertaken in which the robot was ordered to move along different weakly ventilated corridors, while keeping track of its center (framing a '1D' scenario). The measured sensor values show evident peaks that roughly indicate the location of the odour source, if the robot moves with a speed not too low. In this case the system proved to be well suited to detect even weak odour sources. Otherwise the observed course of the received values show many peaks hardly correlated with the location of the odour source. Several investigations were performed to clear up this behaviour but it is still not possible to make concluding statements about the reasons. Finally the setup to perform experiments in a '2D' scenario is described and concerning results of first investigations are presented. It was shown that the utilized system is also capable of detecting a distant odour source in a 2D environment and that the somewhat harder localization task has to account for some weak airflow even in closed, unventilated rooms.