Sergio Perez there is “still an issue” with his Force India after struggling during third practice and qualifying for the United States Grand Prix.
The team discovered a problem with a component at the rear of his car during third practice but Perez felt something was still not right during qualifying.
He lagged behind team-mate Nico Hulkenberg throughout the session, eventually being knocked out in Q2.
Perez will line up for the race at the Circuit of the Americas from 11th place on the grid after a difficult Saturday.
“It has been a messy day – not only qualifying, but final practice as well,” he said. “For some reason, I’ve been quite a long way off the pace and we’ve lost some of the performance we had yesterday.
“This morning we found an issue with one of the components at the rear of the car, which impacted on my pace.
“I thought we had solved that going into qualifying, but I still believe there is an issue with the car because the data showed it was very difficult for me to match my teammate in the braking zones.
“The car also felt nervous through the high-speed corners. Hopefully we can understand where I’m losing out and figure out a solution so that it does not impact on my race pace tomorrow.”
