Exhaust gas analyser for petrol engines equipped with automatic and continuous condensate exhaust system. Automated control of minimum flow and exhausted O2 sensor. Pump water/gas head protection filters placed externally in order to avoid opening the appliance for normal maintenance. Automatic self-zero and automatic compensation of ambient pressure. Its strength lies in the extreme ease of use guaranteed by the minimal encumbrance of the instrument and the clear and intuitive management software graphical interface.