diff --git a/coreneuron/mechanism/eion.cpp b/coreneuron/mechanism/eion.cpp
index 25422326..11b2e150 100644
--- a/coreneuron/mechanism/eion.cpp
+++ b/coreneuron/mechanism/eion.cpp
@@ -316,6 +316,7 @@ void nrn_init_ion(NrnThread* nt, Memb_list* ml, int type) {
 int _cntml_padded = ml->_nodecount_padded;
 pd = ml->data;
 ppd = ml->pdata;
+ printf("nrn_init_ion %d %s conci %lf conco %lf charge %lf celsius %lf\n", type, nrn_get_mechname(type), conci0, conco0, charge, celsius);
 // There was no async(...) clause in the initial OpenACC implementation, so
 // no `nowait` clause has been added to the OpenMP implementation. TODO:
 // verify if this can be made asynchronous or if there is a strong reason it

# build NEURON with CoreNEURON using master and this branch and compare the output of the following
git clone -b magkanar/debug_ions git@github.com:neuronsimulator/ringtest.git
<install_dir>/bin/nrnivmodl -coreneuron mod
mpirun -n 2 ./x86_64/special -mpi -python ringtest.py -dumpmodel
mpirun -n 2 ./x86_64/special-core --mpi -d coredat