Comparison of STIS and COS spectra surrounding the region of the Si IV emission line. The black histogram shows the average STIS 2001 spectrum. The blue histogram is the unweighted average COS spectrum from 2016. The solid red line is the best-fit emission model for the COS spectrum. The velocity scale along the top axis is for Si IVλ1393.755, relative to the host galaxy systemic redshift, z = 0.00973 (Theureau et al. 1998).