Kimi Raikkonen admitted that his Lotus struggled to get heat into the Pirelli tyres during Friday's free practice.
In the cold conditions in Montreal on Friday several teams struggled to get their tyres to perform and the former World Champion was fearful that conditions wouldn't improve during qualifying.
"Obviously the lap time was not the fastest but it's very close here between everybody so if you go faster you can gain a lot of places," the Finn noted after finishing 11th in practice.
"The car is not too bad but we have some issue with getting the tyres working.
"If we can get the tyres to switch on it makes a much bigger difference than any small set-up thing.
"It's the same story as in Monaco. We were pretty OK but we were not fast enough in qualifying because of the tyres not working.
"If we can get the tyres working, it makes a massive difference."
Apart from struggling with the Pirellis, Raikkonen believes the rest of the car is running optimally.
It's not too bad but the feeling is that if we can switch the tyres on it will go better," he added.