Max Verstappen has lashed out at Renault.
In Hungary, the Dutchman was the latest to suffer due to a reliability problem with his Renault power unit.
For 2019, Red Bull is switching to Honda.
"We pay millions for this engine. But what we get is just sh-t," Verstappen told Bild newspaper, following his foul-mouthed radio tirade.
The 20-year-old said that, in addition to poor reliability, "We lack power".
Also furious was Verstappen’s boss Christian Horner.
"I guess we shouldn’t be surprised anymore," he said in Hungary.
"But we pay Renault many millions for these engines and it’s not a premium product."