Renault insists customer status is not hurting the Lotus Formula 1 team, as problems with the reliability of the E22 continued in Malaysia on Friday.
After a troubled pre-season and difficult opening race in Australia, Romain Grosjean and Pastor Maldonado completed just 20 laps between them in Friday's free practice sessions for the Malaysian Grand Prix, while factory Renault squad Red Bull managed 88 laps and sister squad Toro Rosso 101.
Renault's head of track operations Remi Taffin said the French manufacturer took full responsibility for the power unit problem that kept Grosjean out of FP1, but insisted the Enstone team is not losing out by having a different working relationship with its engine supplier.
"No, they will get to the last 10 per cent, whether they are 91 or Red Bull is 98," Taffin told AUTOSPORT when asked if Lotus is losing out by being a customer team.
"They will get there and the last five or 10 per cent is up to each individual team.
"If we only talk about the power unit they will get to the same level. There is some stuff - the installation, the cooling, the exhausts, energy - that is different for the way the power unit is installed and operated in the car [compared to other Renault teams].
"All in all, Lotus should have the same power unit condition as a Red Bull or a Toro Rosso. It's just up to us to make it consistent at Lotus.
"The engine is much more together and more driveable. We will soon be at the same level with them as the other teams.
"I hope tomorrow we will see the pace of the Lotus. We just need to make them run."
Grosjean, who broke a gearbox cable and then the bearings in his car's gearbox in FP2, said Lotus' lack of resources compared to bigger teams was making troubleshooting its problems more difficult.
"We have less people working on issues, plus we have the double problems that the engine is not always working and is not reliable enough," he said.
"Today one session is entirely due to Renault, the other one is our issue.
"If our car is running and Renault brings us some more performance and reliability, and we do our homework, we can catch up.
"We won't be fighting for the podium in two races but we can certainly get to a decent level."
Team-mate Maldonado, who was delayed by a battery issue in FP1 before a turbo failure put him out for the day, urged Renault and Lotus to stay united in the face of adversity.
"We have been working so hard, all together with Renault trying to fix all the problems, but [we have been] a bit unlucky," Maldonado said.
"The situation is a bit worrying but it's not down to one team or one department.
"It's not all Lotus, it's not all Renault, it's a team. We must be together to solve the problems."