Renault F1 engine still feels the same, says Red Bull's Ricciardo

The French manufacturer made some headway with its troubled engine last year, and has increased its investment to coincide with its return as an F1 constructor in 2016.

During the launch of that programme in Paris last month, managing director Cyril Abiteboul called Renault's winter upgrade its biggest since the introduction of the current hybrid power units in 2014.

But during the first day of 2016 running at Barcelona, Ricciardo could not detect any notable difference between the new unit and what he finished 2015 with.

When asked by Autosport how the engine felt, the Australian said: "It pretty much feels like we ended last season.

"Which isn't a bad thing, I think on day one it's a lot better platform to work from than what we had this time last year.

"There wasn't any whiplash or anything like this... but I'm a bit happier and it's a good start, it's probably all we can ask for, for now."

Ricciardo finished the opening day in third place, 1.105 seconds behind Ferrari's pacesetter Sebastian Vettel, having completed 85 laps.

He hopes more performance will come from the unit, either later in this week's test or during the second group of four days at the Catalunya track in March, when the focus moves away from reliability.

"We are still not on race trim, in terms of power, and we don't have all of the bolt-on bits on it at the moment," he added.

"For now it is as expected.

"The team did say 'expect something similar to last year', for the first test at least.

"It's pretty much that for now. I would say it's a decent start."

Team boss Christian Horner expects Red Bull to start the season behind sister squad Toro Rosso, with Carlos Sainz Jr calling that team's year-old Ferrari engines "a very decent step" over the Renault he used in 2015.