  New experimental data on the pd -> 3He pi+ pi- reaction obtained with the
COSY-MOMO detector below the three-pion threshold are presented. The reaction
was also studied in inverse kinematics with a deuteron beam and the higher
counting rates achieved were especially important at low excess energies. The
comparison of these data with inclusive pd -> 3He+X rates allowed estimates
also to be made of pi0 pi0 production. The results confirm our earlier findings
that close to threshold there is no enhancement at low excitation energies in
the pi+ pi- system, where the data seem largely suppressed compared to phase
space. Possible explanations for this behavior, such as strong p- waves in the
pi+pi- -system or the influence of two-step processes, are explored.
