In this article, the effects of unsteady parameters including mean angle of attack, oscillation amplitude, reduced frequency and pitching axis position on aerodynamic coefficients of a pitching airfoil are studied. The numerical method is described as Coarse Grid CFD (CGCFD) in which the Euler equations are solved using a coarse grid and no slip boundary conditions with compressible surface vorticity confinement technique. The required unsteady time for this method is significantly lower compared to that of the full Navier-Stokes equations with even a simple one equation turbulence model. It is found that the computational time for one oscillation loop is reduced more than fifty times. In addition, a multi zone adaptive spring network is applied to simulate the moving boundary which further reduces the computational time. The obtained numerical predictions are in good agreement with experimental data. In this paper, first, the results are compared with the experiments in two mean angles of attack with specific oscillation amplitude and reduced frequency. Then, the effect of these parameters and pitching axis positions on aerodynamic coefficients of pitching NACA0015 airfoil is investigated. It is observed that moving the pitching axis position to the right or left outside and distancing from trailing edge or leading edge have inverse effects on thickness of the hysteresis loops, the maximum, minimum, and average lift and drag coefficients. Further, increasing the reduced frequency results in a reduction of the lift hysteresis loop slope and the maximum lift and drag coefficients.