Toro Rosso hits back at Renault over reliability issues

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SAO PAULO, Brazil -- Toro Rosso has hit back at Renault after its engine supplier suggested that its spate of recent failures may have been related to the installation of the power unit in the car.

A series of issues at the last two rounds has led to a significant amount of grid penalties for Toro Rosso as well as Brendon Hartley's failure to finish in Mexico. Both Toro Rosso drivers are due to drop places this weekend after requiring more new power unit components ahead of practice, with further issues detected on both cars during Friday practice.

Speaking to Motorsport.com on Friday, Renault boss Cyril Abiteboul suggested the incidents may be linked to the way Toro Rosso is running its power unit.

"We are not happy with that situation, and we take it very seriously," he said. "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.

"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."

In a statement released to the press on Saturday morning, Toro Rosso hit back at its engine supplier, blaming a lack of new parts for the persistent failures.

"Due to recent accusations made in the media from the team's engine supplier, Toro Rosso wishes to clarify the actual situation regarding the power units," the statement read.

"It comes as a big surprise to the team that Cyril Abiteboul has suggested to the media that the problems Toro Rosso suffers with the power unit are primarily team related, and the way in which the power unit is operated in the STR12 chassis.

"We would like to clarify that all the MGU-H and Shaft failures Toro Rosso has recently suffered are not associated with how the team is operating or with how the PU is integrated in the chassis.

"Nothing has been changed or altered in this installation during the 2017 season, other than cooling improvements mid-season. Since the summer break Toro Rosso has suffered continuous power unit related failures, and the resulting grid penalties has cost the team points and relative positions in the Constructors' championship.

"One of the primary reasons for the issues we are seeing is the lack of new power unit parts available. In Toro Rosso's case the team is constantly having to change parts from one PU to another during the weekend and, on many occasions, is forced to run old specification assemblies.

"The last race in Mexico saw only two cars out of six finish the race, highlighting the poor reliability.

"We mustn't forget that they are fighting with Toro Rosso for a better position in the Constructors' championship, as suggested by Mr Abiteboul the situation may not be a coincidence, but it is certainly not due to STR's car."

Toro Rosso, in sixth place, is just five points ahead of Renault in the constructors' standings with two rounds remaining. Positions in the championship at the end of the year are directly linked to prize money payments the following year.

The current spat is the latest in a long list of disagreements between Renault and Toro Rosso's parent company Red Bull, and Abiteboul was spotted in a heated debate in the middle of the paddock with Red Bull boss Helmut Marko on Saturday morning. Although Renault will continue to supply the senior Red Bull team with engines next year, Toro Rosso will switch to Honda in 2018.