High strength steels like API X-80 shows excellent mechanical properties for transmission pipeline applications in oil industry, however when exposed to sour gas and aggressive species in solution the mechanical strength decreases. Low pH values in solution consider hydrogen ion concentration in the electrolyte, like in H2S(aq) brine at pH=4 typically used to simulate sour ambient existed in produced water in oil platforms. The hydrogen ion and H2S(aq) decomposition reaction result in sulfur based corrosion products formed at the interface of the steel-solution in the form of film layers. Sulfur corrosion products have semiconductor properties that decrease the current flow distribution through the electrode- electrolyte interface; but the dissolution process may be favored due to the poor adherence and porous number and distribution of the films. Imidazoline used as corrosion inhibitor in acidic environments is characterized for different concentrations. EIS and Cyclic Voltammetry were used to follow the interfacial reactions that permit to understand the mechanism associated to the formation and chemical properties of the steel-sour electrolyte interface under linear flow conditions.