We present the results of a diagnostic study of the use of coherent four wave mixing for in situ measurement of an electric field in air or in nitrogen-containing plasmas. Static electric fields in air at a nominal pressure of $625\mathrm{Torr}$ and temperature of $300\mathrm{K}$ are detected using vibrational CARS of nitrogen. It is shown that the ratio of the infrared signal to the vibrational ${\mathrm{N}}_2$ CARS signal is equal to approximately ${10}^{-8}$ at $8.33\mathrm{kV}/\mathrm{cm}$ , a factor of approximately 50 less than that predicted assuming equal third-order nonlinear susceptibilities. It is also shown that the spatial resolution of a typical collinear geometry measurement is approximately $1\mathrm{cm}$ . Finally, it is shown that achieving sensitivities of the order of $1\mathrm{kV}/\mathrm{cm}$ requires that the coherent Raman pumping be performed in the highly saturated and Stark broadened regime.