Red Bull's Mark Webber is under investigation by the United States Grand Prix stewards for allegedly missing a weight check in qualifying. Race officials said the incident happened near the end of Q1.
Webber qualified third on the grid, two places behind teammate Sebastian Vettel.
"I'm happy with the last part of Q3," the Australian said at the end of qualifying. "I had to manage a little problem in Q3, and did a strong lap time. I would have liked to have had more pace but I'm happy with third on the grid, and we can have a very strong grand prix from there."