It was also their first win on Australian soil in almost a year, following a round 22 result at the same venue in 2016.
It was a vital victory, although soured by Kieran Foran's quad injury, as the five-eighth limped off in the 63rd minute.
"I felt a bit of a twing and wasn't too sure what it was," Foran said after the match. "The doc checked it out ... he thinks it's not too bad. We've got a long turnaround now, so hopefully I'm right for the next game."
But regardless, the Warriors' prospects look a lot healthier this morning, with a bye next week, then a home match against the Bulldogs.
The team, backed into a corner after three losses in their last four games, responded with one of their best efforts of the year. They led 24-4 at halftime, after a three-try burst in seven minutes close to the break, and finished the job with composure in the second spell.
Shaun Johnson responded to recent criticism with a strong display, including three try assists, while the forward effort was impressive, from veterans Ryan Hoffman and Simon Mannering to greenhorns Sam Lisone and Bunty Afoa.
The visitors were aided by an inaccurate Titans display, with highly-rated half Ash Taylor having a nightmare.
After an early Titans try, the Auckland club stamped their mark on the contest. They were urgent on defence and smart with ball in hand. They played solid football, but with variety, including the pleasing addition of support runners, which has often been a rare thing this season.
And most importantly, there was genuine mongrel; an attitude that nothing was going to be left in the tank, no fuel for regrets on the long journey home today. That combination of attitude and execution produced four first-half tries, with David Fusitu'a centimetres from a fifth.
The home side were their own worst enemies. They threw passes over the sideline, fumbled easy balls and gave up soft penalties, although it was often a product of Warriors pressure. Coach Stephen Kearney's side then flicked the switch, sparked by some bench impact, as Blake Ayshford, Ken Maumalo and Roger Tuivasa-Sheck crossed.
The Titans were always going to respond, and got some early second-half momentum from a Jarryd Hayne try. Johnson ran the second half show expertly, while Ata Hingano was a crucial option off the bench and grabbed his first NRL try.
Hoffman capped his special occasion - becoming the 27th NRL player to reach 300 games - with an unlikely conversion after the final whistle.
Warriors 34 (R. Hoffman, B. Ayshford 2, K. Maumalo, R. Tuivasa-Sheck, A. Hingano tries; I. Luke 4 goals, R. Hoffman goal) Titans 12 (K. Elgey, J. Hayne, D. Copley tries). Halftime: 24-4.