Houston answered within five minutes as Davis made amends for his foul in the box by firing an equalizer in the far bottom corner from the edge of the box.
Giles Barnes handed Houston the lead in the 32nd minute by drifting in from the left flank and ripping a shot just inside the far post, and Will Bruin extended the lead just before the halftime interval with a right-footed shot from the center of the box.
The emphatic victory was sealed in the 69th minute after Bruin was fouled in the box by Tim Melia. The Chivas goalkeeper was sent off for denying a scoring opportunity and Barnes converted the ensuing penalty to put Houston's victory beyond any doubt.
The Dynamo (3-4-2) see their six-game winless run come to an end while Chivas (1-5-3) slips to the bottom of the Western Conference due to its third straight defeat.