The Japanese manufacturer had spent two development tokens ahead of this weekend but experienced a new raft of reliability woes at Montreal, with team-mate Fernando Alonso also having to change engine during free practice.
“Initially it was an electronic issue and then that caused a problem with the ICE [internal combustion engine],” said Button. “It’s difficult but we’ll deal with it and the guys are doing a fantastic job of taking the car apart and putting it back together.
“We pretty much knew we would not make it for qualifying. I don’t know what’s going to happen tomorrow yet, where I am going to start from, how much of a penalty I’ve got. There are lots of different things we need to look at for the moment.”
Although Honda motorsport boss Yasuhisa Arai says the new upgrades look to improve both reliability and performance, the MP4-30 also struggles in terms of outright pace, as highlighted by Alonso’s lowly P14 in qualifying.
Still lacking straight line speed, the 2015 McLaren-Honda challenger is yet to make its maiden Q3 appearance this year. Around a typical power track like Circuit Gilles Villeneuve, Button thus braces for a challenging race on Sunday.
“I don’t think I’ll be able to overtake many cars tomorrow. I think I’ll be a long way behind, also because of the penalty we’ll incur in the race – either a stop-and-go or a drive-through I’m not sure yet. We’ll have to see but it makes the race… long.
“It will be a tough day but we’ll do the best we can.”
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