Flash photolysis of Cl-2/CF3CHO/M gas mixtures (M = N-2, SF6) combined with transient diode laser detection of CO is used to investigate the kinetics of the CF3CO + M --> CF3 + CO + M dissociation reaction and the competition with the CF3CO self-reaction. The studies are carried out over a temperature range 223-353 K and a pressure range 25-650 Torr. The temperature dependent low- and high-pressure-limiting rate constants in N-2 are given by k(2,0) = (3.9 x 10(-11))e(-(2550+/-650)/T) Cm-3 S-1 and k(2,infinity) = (1.5 x 10(11))e(-(4240+/-660)/T) S-1, respectively, with F-c = 0.6. Essentially the same high-pressure rate constant is obtained for a bath gas of SF6. These results clarify a previous discrepancy of about 10 kcal/mol in the activation energy. As part of this study, we report a rate constant of k(3) = (2.5 +/- 1.5) x 10(-11) cm(3) s(-1) for the reaction CF3CO + CF3CO --> (CF3CO)(2) and a rate constant of k(4) = (6.1 +/- 2.5) x 10(-13) cm(3) s(-1) for CF3CO + Cl-2 --> CF3C(O)Cl + Cl. Both are essentially independent of temperature over the range 223-353 K.