Pierzynski ignited the outburst with a two-run single and later added another RBI hit as Texas sent 14 men to the plate, banging out seven hits, drawing three walks and benefiting from two Astros errors.
The 11-run uprising was the most by a team in a single inning this year and the first time the American League West-leading Rangers have scored that many since 2009.
The Texas catcher finished 4-for-4 with four RBI and a homer. Ian Kinsler drove in three runs and Leonys Martin contributed three hits, two RBI and three runs scored for the winners.
Matt Garza (3-1) notched the triumph despite yielding five runs on eight hits over 6 2/3 innings. He walked one and struck out six.
Houston's Lucas Harrell (6-14) was torched for nine runs (seven earned) on seven hits, lasting just 2 1/3 innings.
Robbie Grossman provided two RBI for the Astros, who dropped the opener of a three-game set.