  Faced with unresolved tensions between neutrino interaction measurements at
few-GeV neutrino energies, current experiments are forced to accept large
systematic uncertainties to cover discrepancies between their data and model
predictions. In this paper, the widely used pion production model in GENIE is
compared to four MINERvA charged current pion production measurements using
NUISANCE. Tunings, ie, adjustments of model parameters, to help match GENIE to
MINERvA and older bubble chamber data are presented here. We find that
scattering off nuclear targets as measured in MINERvA is not in good agreement
with scattering off nucleon (hydrogen or deuterium) targets in the bubble
chamber data. An additional ad hoc correction for the low-$Q^2$ region, where
collective effects are expected to be large, is also presented. While these
tunings and corrections improve the agreement of GENIE with the data, the
modeling is imperfect. The development of these tunings within the NUISANCE
frameworkallows for straightforward extensions to other neutrino event
generators and models, and allows omitting and including new data sets as they
become available.
