The paper provides an approximate solution of the coupled nonlinear equations of the flow of a rarefied gas that takes place next to a vertical infinite porous plate. The solution of this problem was carried out under the conditions of constant suction speed, at the speed of the first order and the boundary conditions of sudden temperature change, in the presence of free current with constant non-zero averaging. Profiles of average speed and temperature are shown on the graph, and numerous values: $T_m$ (— average surface friction), $q_m$ (— average speed of thermal conductivity), $B$ (— amplitude of surface friction), tan $\alpha$ (— phase of surface friction), $|Q_1|,|Q_2|$ (— the amplitudes of the first and second harmonics of the heat conduction speed), tan $\alpha_1$ and tan $\alpha_2$ (— the phases of the first and second harmonics) are given in the tables. The mean speed increases with $\omega$ at $G\gtrless0$ ($G>0$ — when cooling the plate; $G<0$ — when heating the plate). The mean temperature increases with increasing $\omega$ for $G>0$, and decreases with increasing co for $G<0$.