The Portable Automobile Soot Analyzer, the opacity meter, device is used to measure the amount of opacity of exhaust gas emissions from gasoline or diesel fueled engines due to production of soot from their combustion. This device observes the amount of exhaust gas mixture opacity by radiating a laser beam and, so, obtaining the absorbance amount of the certain frequency of the laser beam. The final measured opacity will be a value between 0 to 100 percent. It counts the Particles Numbers of the exhaust gas stream as well. The PASA, also, have another capabilities including using rechargeable batteries instead of on-grid electricity power, displaying data on the LCD, printing them on the paper by the on-mounted micro printer