Lewis Hamilton says he is in a "better position" with his race starts after working on the problem between the Japanese Grand Prix and this weekend's race in the United States.
The Mercedes driver has suffered from poor starts this season, most recently in Suzuka where he dropped from second to sixth before the first corner, allowing team-mate and championship leader Nico Rosberg to go unchallenged during the race to extend his lead to 33 points.
With just four races remaining to close that gap, Hamilton revealed that he and his engineers have been working on race starts to minimise any unecessary lost points.
"It has been an ongoing thing all year long," he said. "There’s been a lot of changes, a lot of work, perhaps more than in other areas.
"I was at the factory last week and we were working very hard to cover up all areas so we hope that we have a slightly better formula this weekend.
"If not, then there will be a better formula next weekend, but it is something that… I definitely feel that we’re in a better position so fingers crossed for Sunday."
Meanwhile Hamilton confirmed his foot injury is no longer a problem, after it forced him to miss a recent Pirelli tyre test.
"I am 100 per cent, yeah, feeling great," he added. "I basically had an injury that I’ve been carrying generally all year long, in both feet. Just induced by running.
"Unfortunately the physio said that it just takes a lot of stretching and it just heals over a long time.
"At the time I woke up in the morning, I was feeling quite a lot of pain the day before, and it hadn’t diminished, so there was very little… the most important thing was to be fresh for here and feeling better for here. This is actually the first week that it’s felt good."
