  Precession in Binary Black Holes (BBH) is caused by the failure of the Black
Hole spins to be aligned and its study can open up new perspectives in
gravitational waves (GW) astronomy, providing, among other advancements, a
precise measure of distance and an accurate characterization of the BBH spins.
However, detecting precessing signals is a highly non-trivial task, as standard
matched filtering pipelines for GW searches are built on many assumptions that
do not hold in the precessing case. This work details the upgrades made to the
GstLAL pipeline to facilitate the search for precessing BBH signals. The
implemented changes in the search statistics and in the signal consistency test
are then described in detail. The performance of the upgraded pipeline is
evaluated through two extensive searches of precessing signals, targeting two
different regions in the mass space, and the consistency of the results is
examined. Additionally, the benefits of the upgrades are assessed by comparing
the sensitive volume of the precessing searches with two corresponding
traditional aligned-spin searches. While no significant sensitivity improvement
is observed for precessing binaries with mass ratio $q\lesssim 6$, a volume
increase of up to 100\% is attainable for heavily asymmetric systems with
largely misaligned spins. Furthermore, our findings suggest that the primary
cause of degraded performance in an aligned-spin search targeting precessing
signals is not a poor signal-to-noise-ratio recovery but rather the failure of
the $\xi^2$ signal-consistency test. Our work paves the way for a large-scale
search for precessing signals, which could potentially result in exciting
future detections.
