The Finn's DS3 WRC was seven tenths of a second up on M-Sport Ford driver Evgeny Novikov.
Novikov's fellow Fiesta RS WRC drivers Thierry Neuville and Mads Ostberg were joint third quickest, 3.2s down from Hirvonen's benchmark.
"So far so good," said Hirvonen at the end of the stage. "It's the perfect start. Now we have to continue this for the rest of the stages. We had a clean run, no problems."
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Ogier secures Mexico victory
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Hirvonen is expected to select 13th position on the road for Friday's opening day of stages, allowing those World Rally Car drivers slower than him through the qualifier to sweep the surface clean.
"Running order is really important here," said Hirvonen. "With a hard surface and dry conditions, it's important to be as far back as possible on the road."
The factory Citroens and M-Sport cars ran on soft-compound tyres, while Volkswagen elected to take the hard Michelin for the three-mile stage, a decision that surprised Hirvonen.
Sebastien Ogier was the fastest VW driver in fifth, 3.9s off the pace and two places ahead of team-mate Jari-Matti Latvala.
"We talked about the tyre choice," said Ogier. "And the decision was to go on the hard tyre, maybe the soft was quicker. We were first on the road, so we were cleaning it a little bit."
Latvala added: "This event is a lot about tyre management, we'll see at the finish who got it right today."
Mexico Rally
Ostberg's Mexico victory bid ends
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Mexico Rally
VW: Mexico no disaster for Latvala
09/03/2013 AT 16:37