By Abhishek Takle
SHANGHAI (Reuters) - Renault have warned Red Bull and Toro Rosso to expect more pain in Bahrain after both Formula One teams suffered power unit problems in China on Sunday.
Former champions Red Bull scored just two points in Shanghai while their sister team drew a blank after engine-related retirements.
Daniil Kvyat's race ended spectacularly with the Russian pulling up with smoke spewing from his Red Bull, while Toro Rosso's Max Verstappen brought out the safety car three laps from the end when his car halted on the main straight.
"As a company, we hold our hands up when it's our problem, and today that was the case," said Renault managing director Cyril Abiteboul.
"We have to investigate the reasons for the failures and put in place countermeasures for 100 percent reliability as quickly as possible. With just five days to go, we know that Sakhir (the Bahrain circuit) will be another test for us."
Abiteboul said Renault had feared problems in the early races and the plan was to be in Monaco in May "with absolutely no reliability issue any more."
Renault and Red Bull, who won four drivers' and constructors' championships together between 2010 and 2014, have had an uneasy relationship of late and both sides have talked about walking away from the sport.
The French manufacturer struggled to come to terms with the new V6 turbo hybrid power units last year, although Red Bull did win three races, and are still behind rivals.
On Sunday the two sides presented a united front, however, with Red Bull principal Christian Horner and Abiteboul holding a joint post-race briefing.
"At the moment if you look on the facts of where we are, we're not in a great situation," Horner said. "But Viry (Renault headquarters) has got a long history of success in Formula One and they've still got some very capable people there."
Horner said the priority was to help Renault find a solution by offering as much support as possible.
Red Bull's Australian driver Daniel Ricciardo, who finished ninth after dropping down the field due to a poor start, said the problems would likely result in penalties with the rules currently limiting drivers to four engines a season.
Ricciardo was already running his third engine of the season in China while Kvyat has also been romping through his allocation.
"We're going to get copped with at least one (penalty)," Ricciardo told reporters.