The Galaxy will meet the winner of the Eastern Conference final on Saturday between Chicago Fire and Real Salt Lake City in next Sunday's final in Seattle to determine the MLS champions.
The floodlights went out in the 18th minute, causing an almost 20-minute break, and the same happened again six minutes after the interval with stadium officials blaming the local grid for the failure.
Houston came close to taking the lead in the 78th minute when Brian Ching's header was spectacularly tipped over by L.A. keeper Donovan Ricketts and from the resulting corner Andrew Hainault headed home but the effort was ruled out for an infringement.
"There is nothing wrong with a bit of controversy in a club - it brings players together and it did that," he told ESPN television.
"Its so important for us to do well, we have had so many disappointments over the past four years ... we have a great bunch of guys who work hard for each other," he added.
