Kamui Kobayashi admits Sauber face an uncertain time in Valencia as the team doesn't know how their C31 or its Pirelli tyres will deal with the heat.
Last year the temperature averaged about the 47°C mark for the 57-lap grand prix, one of the hottest Sundays on the Formula One calendar.
This year the teams are expecting much the same, which could pose a problem for their Pirelli tyres which are known for being very sensitive to the temperature.
"In Valencia it is usually very hot. I personally like that, but it is difficult to say what it means for the car and the tyres," the Sauber driver said.
"It will be tough, that much is certain.
"Tyre management will be the key, together with a good race strategy. The street circuit also requires a decent amount of downforce for the car."
The 25-year-old finished seventh at the 2010 edition having started P18, which meant he spent the better part of the 57 laps cutting his way through the traffic.
Last year, though, he was not able to repeat that achievement as he started P14 and dropped two positions by the end of the grand prix.
"Overtaking is not easy but not impossible either," Kobayashi said. "In 2010 it was actually good fun.
"My target is a strong qualifying as well as a strong race."
Further explaining the problem with the heat, Sauber's head of track engineering Giampaolo Dall'Ara said: "In Valencia we have to expect high temperatures at this time of the year, so the tarmac can get very hot.
Pirelli is supplying us with the medium and the soft compound tyres, which have changed a bit since last year and may need us to look at a slightly different strategy for them. Rear degradation could be an issue."