Driving an LPG car is not significantly different to using a conventional car. The controls remain largely unchanged: starting, engaging and stopping the engine are all done in the normal way. The main additions are a switch, usually located by the gear lever or on the dashboard, which enables the driver to select auto gas or petrol operation, and a fuel gauge that shows the remaining amount of both fuels. However, compared to petrol performance, drivers of bi-fuel cars may notice a small loss of power at full throttle when in gas fuel mode. Under most driving conditions, however, the difference is hardly discernable.