We have studied the influence of substrate orientation and dopant on the growth kinetics of Pd2Si. Both 100- and 111-oriented Si wafers with P concentration in the range of 5×1013 to 4.8×1018 cm-3 and with As concentration in the range of 2.8×1019 to 5×1020 cm-3 have been used. Doping concentrations of the Si substrate below 1019 cm-3 do not affect the growth kinetics but a significant influence is found for As doping levels exceeding 1019 cm-3. For As concentrations of 5×1020 cm-3 the activation energy is lowered by about 0.35 eV and the preexponential factor is lowered by 3 orders of magnitude. These changes are independent of the Si substrate orientation. The results have been combined with earlier results of marker motion to interpret the vacancy mechanism of diffusion in Pd2Si.