Translation energy loss (TEL) spectra for NO2+· in collision with helium were obtained using the methods of O'Keefe et al. [2]. The results are in generally satisfactory agreement with the previous work, and are compared with other information on states of NO2+·, particularly data from double-charge-transfer spectroscopy which are in serious disagreement with the present and previous TEL results. In the course of the present work and in other translational energy studies in this laboratory, a problem, inherent in TEL spectroscopy conducted on a double-focusing mass spectrometer, that can lead to spurious peaks, became apparent and is discussed.