Daniel Ricciardo says Renault needs to look in to a "change of direction" if it remains as Red Bull's engine supplier.
The Renault power unit has been largely uncompetitive over the last two seasons, with Ricciardo winning three races in 2014 but managing just two podiums so far this year. With Red Bull originally moving to terminate its contract with the French manufacturer, it now appears the partnership will continue in to 2016 but a recent test of a power unit has concerned Ricciardo.
"Yes it is definitely obvious that they have some work ahead of them," Ricciardo said. "Pretty much everyone has turned us down, so I don’t think that they are out of the picture. We will see what happens. We put the D-spec engine in Brazil and it didn’t really show a whole lot so there would need to be some change of direction."
And Ricciardo is unsure whether Renault will look to further develop the latest version of its power unit.
"I’m not sure. There can be a lot [of improvements] but in terms of where or what, I am not sure. We are choosing not to run it this weekend. I think it is something that will need time. Whether they try and refine that or start something completely different, I have no idea."
Having confirmed he will revert to an old specification of the Renault engine this weekend, Ricciardo believes it will at least give him a straight fight against team-mate Daniil Kvyat - who did not run the update at the last race - in the battle for seventh in the drivers' championship.
"I think so, as least it is something that we know and Danny’s weekend wasn’t too bad in Brazil. At least it is even, and there is no 'he’s got this and he’s got that'. So put both in the car and then neither of us as any reasons to complain or make excuses."
Unfinished business: the scores still to be settled in Abu Dhabi
Chris Medland's Abu Dhabi Grand Prix preview
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