Ferrari team principal Maurizio Arrivabene says the SF16-H has an "endemic problem" when track temperatures rise.
Ferrari has often shown promising pace in practice sessions, only for it to disappear relative to its rivals when it comes to qualifying. At the last round in Mexico, Sebastian Vettel topped second practice but could only manage seventh on the grid when temperatures spiked the following day for qualifying and he bolted on the super-soft tyres.
"What was wrong in Mexico was the endemic problem that we have all year long," Arrivabene said. "You remember in Baku and in Spain and Monaco, when the temperature goes up to the sky we have problems.
"We are making an analysis of that and now it is quite clear the reason why, so we are working on that."
Vettel finished Mexican Grand Prix in a battle for third with the two Red Bulls. Although he was later demoted to fifth, Arrivabene says Ferrari's fightback in the race was proof of a change at the team.
"I think the most important thing is that the team is reacting very well. I'm not happy because we did not win the race, but we demonstrated the character of the team and on top that something is moving. This is important for me because I was receiving all the radio communications and everybody was doing their job.
"The guys on the pit stop were perfect, not incredibly quick, but perfect in the way they were doing what we asked them to do, and the team demonstrated they were fighters and this is what I was asking for."