The Portuguese driver topped the timesheets when the session was red-flagged three minutes before the end and not resumed, following an incident involving Darryl O'Young.
Mehdi Bennani made a strong start with a lap of 2:38.340, but his mark was swiftly bettered by Stefano D’Aste’s 2:38.300 and Monteiro’s 2:38.037.
Halfway through the session, Bennani regained the lead with a lap of 2:36.853, before Rob Huff set the first significant improvement being with a time of 2:34.789.
But Monteiro then made his mark with a 2:33.908, which was still more than three seconds slower than last year’s pole position time.
D'Aste set the second fastest lap of 2:34.528, while Huff ranked third.
The session was red-flagged when O’Young spun at the Mandarin Oriental bend and crashed into a barrier.