Renault: Toro Rosso failures not coincidence
Renault believes the high rate of power unit failures suffered by customer Formula 1 team Toro Rosso recently is no "coincidence".
Pierre Gasly and Brendon Hartley both started the Brazilian Grand Prix weekend with 10-place grid penalties after taking new MGU-Hs, the eighth of the season for their respective cars.
However, Gasly's component failed after just one flying lap, while Hartley stopped on circuit with a turbo shaft failure on the outlap of his first proper run.
Gasly is now set to lose a further 15 places on the grid for a replacement MGU-H and turbo, while his team-mate's penalty situation is currently not clear.
This comes after a Mexican GP weekend in which Gasly sat out most of practice and all of qualifying, and Hartley suffered failures in qualifying and the race.
"We are not happy with that situation, and we take it very seriously," Renault's Cyril Abiteboul told Autosport.
"Toro Rosso has suffered in the last couple of events much more issues than other teams, and obviously when it's happening, because of the regulations, and because of parts availability and production lead time, that's causing issues."
He added: "We do have a little bit of a concern about the way that our engine is operated in the Toro Rosso car, which may explain why we have had so many issues coming from Toro Rosso specifically.
"There are never coincidences in this sport."
The problems have come at a critical time as Toro Rosso is just five points ahead of Renault in the world championship, and six ahead of Haas.
Team principal Franz Tost is convinced Toro Rosso is not to blame.
"It's worrying," he told Autosport. "Everything is the same in the installation, nothing has been changed since the beginning of the year.
"From Toro Rosso's side, regarding the car, there's no part from the chassis connected to the MGU-H that has caused anything.
"There's nothing we can do, just see which parts we get, which power unit and so on."
Abiteboul admitted Renault's Viry factory was struggling to keep up with the unexpected demand for extra components.
"We were not assuming that we would have the issues that we have had, and therefore at some point you have to be managing with the parts you have," he said.
"It's only been two weeks since Mexico, we sent the parts back to Viry, we worked on a bank holiday in order to sign off as many of the parts that had seen some issues as possible.
"With the logistics and the timing issues there's a limit to what we can do and the number of new parts that we can bring.
"It's a snowball effect. Once that snowball starts to roll, it's very difficult to stop it.
"We are doing our best in order to contain it, but there will be a limit in the way we can mitigate the consequences of what has happened, which we are still trying to understand."