  We constructed an oxygen abundance map and N/O ratio map of the unusually low
excitation dwarf irregular galaxy NGC 4163 based on publicly available
spectroscopy obtained by the MaNGA survey. We detected auroral emission line
[OII]$\lambda\lambda$7320,7330 which allows us to measure chemical abundance by
direct T$_e$ method. We found that the scatter of the oxygen abundance derived
by the strong line method is large. The oxygen abundances 12 + log(O/H) derived
by strong line method vary from ~7.3 to ~7.8 with a mean value of ~7.55. The
oxygen abundances derived in two apertures of 2 arcseconds by the direct T$_e$
method using our measurements of the O$^+$ auroral line is about 7.8 dex. The
nitrogen-to-oxygen ratio log(N/O) of about -1.5 is typical value for a low
metallicity galaxy, maybe slightly shifted towards higher N/O ratios with
respect to the N/O values in the HII regions in nearby galaxies. An unusual
negative trend between log(N/O) and oxygen abundance is detected. NGC 4163 is a
gas-poor galaxy with a neutral atomic gas mass fraction of around 0.25. The
oxygen abundance in the galaxy is only around 0.1 of the oxygen abundance
potentially attainable in a galaxy with such a gas mass fraction. The low
metallicity coupled with the low gas mass fraction implies that either the
metallicity of the interstellar medium of the galaxy was reduced by pristine
gas infall in the recent epoch or the evolution of this galaxy was accompanied
by strong galactic winds.
