CeCuxAl4-x compounds crystallize in the ordered non-centrosymmeric tetragonal BaNiSn3-type structure (space group 107, I4mm). The strong interaction between crystal field (CF) excitons and phonon modes was observed in parent CeCuAl3. This type of interaction leads to the formation of so called vibron quasi-bound state, which has been observed as an additional peak in the inelastic neutron scattering spectra of only a few other Ce-based intermetallic compounds, e.g. CeAl2 or CePd2Al2. Our recent investigation of CeCuxAl4-x led to the observation of two clear crystal field-like peaks in all investigated compounds (x = 0.75, 0.9 and 1.1). We indent to focus on the development of CF-like excitations with slight Cu-Al substitution (x=0.95 and 1.05) to reveal their shift in energy coming further from stochiometric CeCuAl3.