Observations of Auger transitions to quasi-stable states of CO{++} subsequent to C_1s{-1} and O_1s{-1} ionizations of CO are presented along with the corresponding photoelectron spectra and calculations of the potential energy curves. The equilibrium distances R_e, the vibrational energies homega, and the anharmoncities xhomega, for the final states a (singlet Sigma+), b (singlet Pi), A (triplet Sigma+) and d (singlet Sigma+), are derived from fits to the spectra by assuming Morse potentials. A comparison of these Morse potentials with theoretical potential energy curves reveals excellent agreement in the Franck-Condon regions of the Auger transitions. The relative intensities for the observed C_1s{-1} and O_1s{-1} Auger transitions are also derived.