We have computed the evolution of Z = 10−5 stars of masses between 4 and 9 M , from their main sequence till the late TP-(S)AGB phase.We use a recent version of the Mount Stromlo Stellar Evolution code, in which molecular opacities include the effects of variable C/O abundances ratio, [1]. By computing hundreds (or thousands) of thermal pulses, we have been able either to remove the bulk of the stellar envelopes or to obtain stellar cores very close to MCh. Using [2] prescription for the mass loss rates the computed stars lose their envelopes before their cores reach MCh. This would forbid the occurrence of SN 1.5 for Z = 10−5 stars. Nevertheless the results by [3] suggest that the former prescription might overestimate the mass-loss rates. Therefore we have decreased the rates by [2]. For all the cases we present, even a decrease of one order of magnitude let the stellar cores reach MCh before the envelope is lost. Therefore the occurrence of SN1.5 at Z = 10 −5 and their potential contribution to the chemical evolution of the Universe should not be discarded. We consider the combined effects of the deep/corrosive 2 nd dredge-up and Roche Lobe Overflow (RLOF) during the E-AGB to help to constrain the contribution of massive Z = 10 −5 AGB stars to the CEMPs problem. Our results have implications for the chemical evolution of the Universe and might provide another piece for the puzzle of the CEMPs problem.

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