we need more info...what year and model Civic you have
for 87 and older many were carb'd still with the Si's having MPFI (4 injectors fed fuel in the intake manifold right before the valves - what standard fuel injection is now considered)...some other models may have had a fuel injection setup
for 88-91 the dx, standard had DPFI (2 injectors fed fuel after the tb into the intake manifold)...the si and crx HF models came with MPFI standard
you could have a dx wtih MPFI who a previous owner converted it over making it more confusing
i'm not sure what you mean by auxillary