Nico Rosberg is still trying to get his head around the set-up of his W05 after being sidelined midway through Friday's first practice.
Putting in the laps at the Circuit de Barcelona-Catalunya, Rosberg complained that it was feeling a bit "hot" around his seat.
Heading back into the pits, Mercedes discovered an ERS cooling issue that meant he sat out the second half of FP1.
Back on track later in the afternoon, Rosberg covered 36 laps in FP2 and finished second quickest to his team-mate Lewis Hamilton.
The Championship leader, though, was almost half a second off the pace.
"My hopes are still there that it could still become a normal weekend," he said.
"It wasn't such a massive setback, but yes at the moment we are still running behind a little bit and I haven't found my way with set-up. That's what I'm trying to get my head around at the moment.
"It's just a whole different situation out there again, and every time we go out there I have to adapt to the circumstances and find my way all over again with the setup and optimise it for the conditions and for the track. It's a constant process every weekend and we haven't got there yet.
"It was a difficult start to the weekend and we have a lot of work to do. I'm not feeling so comfortable, but mainly [the problem] in the long run I had a lot of traffic and was always stuck in traffic. That made it very tough and to summarise it, I'm still trying to find my balance."
And on a track where 17 of 23 races have been won from pole position, Rosberg concedes it would be good to be the one to secure Mercedes' fifth pole position of this season.
He told ESPN: "It's a little bit more important, definitely. It's more difficult to overtake here, but still not being on pole, you still have a chance in the race.
"At the start, if you make a good start or whatever, still everything could be possible."