It may be some time before Red Bull perfects its KERS system, car designer Adrian Newey has admitted.
The team did not use the technology to dominate in Australia, while in Malaysia the unit aboard Mark Webber's car failed while teammate Sebastian Vettel drove to victory using his system only intermittently.
"It is a system in its infancy," Newey is quoted by the UK Express newspaper.
Unlike Red Bull, Ferrari, McLaren and Renault ran KERS when the technology was initially introduced in 2009.
"We are not a manufacturer team so we are having to develop it ourselves and on a limited budget, limited resource and limited experience," added Newey.
German Vettel said after winning at Sepang that getting to the bottom of KERS will take "days and weeks" for Red Bull.
We are having to develop it ourselves and on a limited budget, limited resource and limited experience
"We need to analyse the data," he is quoted by Brazil's O Estado de S.Paulo. "It's definitely something we need to focus on because we know we lose time on the track when we have to turn it off.
"For this race (Malaysia) it was crucial because otherwise I doubt I would have maintained my position at the start and the race would have developed very differently," said Vettel.
McLaren's Jenson Button, who finished only 3 seconds behind Vettel at Sepang, insists that Red Bull can be beaten soon.
"In 2002, when Michael won a stupid amount of races - Ferrari were just so fast. I don't think that is the case with them (Red Bull) now," he said.