Q. Does one need to have in mind to comply with the mitzva of Teshuva when reciting Viduy?
A. Kovetz Halochos (26: 10) rules that since it is part of the Biblical mitzva of Teshuva, one has to have intention to comply, otherwise one may not comply. (See also Chaye Adam and Piskei Teshuvos 607: 3)
Horav Shlomo Miller's Shlit'a opinion is that there is a reasoning that one may comply even without the intention of the mitzva, as one complies also when paying back money borrowed or for damages done.
Rabbi A. Bartfeld as revised by Horav Dovid Pam, Horav Aharon Miller and Horav Chanoch Ehrentreu Shlit'a.