The present paper examines the possibility of chemical treatment of old catalysts (a catalyst that has exceeded exhaust limits) for the purpose of improving catalytic efficiency. The proposed method inserts the catalyst in a bath of a strong organic solvent that dissolves oil, soot and fuel residues cleaning the active surface of the catalyst. The preliminary experimental results based on CO, HC and catalyst inlet-outlet temperature difference measurements indicate that after this treatment the catalytic efficiency improves considerably (>30%). Therefore, there are strong indications that if car catalysts underwent a similar treatment at regular service intervals, for example, engine emissions could be considerably reduced and catalyst operational life extended. However more tests under variable engine speed (FTP-test) and load are clearly required in the future, before a definite conclusion can be made.