Ebobisse's tally came from the center of the box after a crossing pass on a header from Larrys Mabiala and garnered the Timbers a point in a stirring comeback.
It was the first draw of the year for Portland but it was more than welcome after a ragged first half. The Timbers are 3-1-1 over their past five matches.
The Dynamo rushed to the front in the 15th minute, with Fafa Picault employing a header to direct home a pass from Maynor Figueroa after a corner kick by Tyler Pasher. Figueroa's blistering shot rebounded off Ivacic, and Picault quickly pounced on the loose ball and headed it home.
Pasher added to the lead in the 33rd minute as he waited in the center of the box for a pass from Matías Vera that he booted into the bottom right corner of the goal.
The Timbers rallied as well in the match statistics, earning advantages in possession percentage (50.4 percent to 49.6 percent), total shots (16-14), total passes (381-379), crosses (19-14) tackles won (10-8) and clearances (26-16). Houston finished ahead in passing accuracy (80.5 percent to 80 percent), shots on goal (4-3), corner kicks (7-4), and duals won (55-46).
The Timbers beat Houston 2-1 on April 24 in Portland in the first meeting of the season for the two teams.