Postpublished at 10:11 British Summer Time 30 September 2017
And Max Verstappen immediately goes second quickest with a 1:31.920, three tenths slower than Lewis Hamilton.
Hamilton on pole, Vettel to start at back following engine problem
Raikkonen 2nd, Verstappen 3rd
Hamilton leads title race by 28 points
Race on 5 live and sport website - coverage from 06:30 BST
And Max Verstappen immediately goes second quickest with a 1:31.920, three tenths slower than Lewis Hamilton.
Max Verstappen is on track and out comes Fernando Alonso. So that's everyone out there now.
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Mark Gallagher
BBC Radio 5 live Formula 1 analyst
We have gone from relatively simple wiring looms to a very complex system that is involved today.
This is very bad news for Sebastian Vettel. It is really going to hamper his progress, not for this session but for the rest of qualifying.
It's all going swimmingly so far for Lewis Hamilton as he puts in a new fastest lap - a 1:31.605 putting him top of the pile with eight minutes left in Q1.
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"It feels like I have no turbo," adds Vettel.
Uh oh.
"I am limping back," says Sebastian Vettel.
Mark Gallagher
BBC Radio 5 live Formula 1 analyst
I don't know enough about the upgrades to know if it's going to materialise in an increased performance.
It has upset Ferrari's engine use plan. They will have to re-calculate to make sure they are not paying for penalties when they don't want to be.
Kimi Raikkonen goes a tenth of a second quicker than Lewis Hamilton to move into P1.
Daniel Ricciardo has just gone out for Red Bull, leaving Max Verstappen and Fernando Alonso as the only drivers to head out.
Few more times on the board with Lewis Hamilton going quickest of all with a 1:32.380.
A high 1:32 is the predicted cut off point to get through.
Romain Grosjean kicks things off with a 1:34.943.
They've done it!
Ferrari have fitted everything into place on Sebastian Vettel's car and he heads on out.
Lewis Hamilton heads out on softs.
The first part of qualifying is under way.
Pascal Wehrlein and Romain Grosjean are among the first out on the track. Both have super-softs on their cars.
Jack Nicholls
Radio 5 live Formula 1 commentator
They are still working on the car. The engine cover is being put on now but it is a little bit touch and go - a little bit closer than Ferrari would have liked.
How's the weather look for the rest of the weekend? Properly mixed.
Find out in the video below.
Rain stayed away for final practice and there's blue sky above Sepang at the moment, although there are a few dark clouds lurking near by.
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Best seat in Formula 1?
John: Definitely Eau Rouge
Andrew Benson
BBC Sport’s chief F1 writer
There is a potential row brewing between some of the leading teams and governing body the FIA, following the resignation this week of FIA technical head Marcin Budkowski. The teams fear Budkowski intends to take up a job offer from Renault - who describe it as “just rumour and speculation” - and this is causing consternation because Budkowski had access to all the teams’ technical secrets. A meeting was convened between bosses of Mercedes, Ferrari, Red Bull, McLaren, Force India and Williams - the strategy group teams - between first and second practice and those in the official news conference were outspoken on the issue.
Horner said: "We take major issue with that if he does end up with another team. Obviously in these individuals you place an enormous amount of trust. In the role that Marcin has been responsible for he has been in an extremely privileged position and extremely recently he has been in people’s wind tunnels and looking at intimate details of knowledge of next year’s cars and I think three months’ notice period for him to then turn up in a competitor team in Formula 1 is entirely inappropriate. I certainly hope that isn’t the case and I’m sure it will get discussed quite seriously at the next strategy group meeting.”
Similar views were expressed by Mercedes’ Toto Wolff, Force India’s Otmar Szafnauer and Sauber’s Frederic Vasseur.
In a Channel 4 interview, Renault managing director Cyril Abiteboul refused to comment on specifics, but said: "We will make sure whatever we do is fair and reasonable and we are open to any discussions on that front.”
Still lots of work going on on Sebastian Vettel's side of the garage.
Ten minutes to go, will they be ready in time?
Feels like an episode of the Crystal Maze.
Need Richard O'Brien to come along and lock them in if they don't get it done in time.
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