Although Renault have made progress in eliminating the problems its power units had during pre-season testing at Jerez and Sakhir, the French manufacturer admitted that its preparations for the Australian Grand Prix are "incomplete".
Renault supplies reigning Constructors' Champions Red Bull, Toro Rosso, Lotus and Caterham with power units, but during pre-season testing their 2014 turbo-powered V6 engines have struggled with performance and reliability.
While Lotus was absent from the first test in Jerez, the other three teams only managed 151 laps during the four days at the Andalucian circuit.
During the two tests in Bahrain that followed, the quartet of Renault-powered teams managed considerable more time on track, but even that improved number was less than half of what the four Mercedes-powered teams managed.
The Renault teams were also considerably slower than their Mercedes counterparts, with reigning World Champion Sebastian Vettel's best time during last Sunday's final day of testing more than four seconds slower than that of the fastest Mercedes driver - Lewis Hamilton.
"We can't escape the fact that we did not complete the entire programme with all the teams and that some Melbourne preparations are incomplete," Rob White, Renault Sport F1's deputy managing director said on the manufacturer's official website.
"On the upside, we have done some of everything, with simulations of qualifying sessions, starts, race distances and long stints and it is fair to say that once again we have made some real progress.
"We have cured or found workarounds for some of the problems we had previously identified. New problems revealed as we ran more have added to the unsolved items, and have disrupted running, which is disappointing for our teams."
White added that Renault would probably be looking for a solution to the torque delivery problems it has been struggling with in the lead-up to the season-opener in Melbourne on March 16.
"Between now and Melbourne we have a number of items to cover," White continued.
"Melbourne will be an anxious weekend. Conducting a normal race weekend, in which both cars run well during each session for every team, would be a great relief.
"I hope we can support our teams and drivers to explore the performance of the car and allow the race to deliver its sporting verdict."