Mercedes team principal Toto Wolff has confirmed the German manufacturer is “listening very carefully” to its engines after suffering two separate reliability issues with its updated ‘2.1’ specification over the French Grand Prix weekend.

Valtteri Bottas became the first Mercedes-powered driver to suffer an issue when he missed the majority of FP2 due to a water leak but his team were able to repair the fault without any lingering impact on the rest of his race weekend.

A similar fate hit Force India’s Sergio Perez during the French Grand Prix when he was forced to retire during the race with a water leak, While Wolff says to the two issues aren’t thought to be linked Mercedes is running a thorough post-race investigation with its updated power unit.

“With a new power unit, you are always listening very carefully and looking at the data what is happening,” Wolff said. “And when one of the six power units has a problem, which we understand was a water leak, a loss of water pressure, so we pitted the car. But you’re listening very carefully what is happening to your own engines.

“We have identified the problem on Valtteri’s car, and we have not seen yet the Perez car and got any conclusions yet.”

French GP - Driver Ratings

Mercedes had initially delayed its engine update when a quality part issue was flagged up ahead of the power unit’s planned debut at the Canadian Grand Prix. Mercedes has described its update as a ‘2.1’ specification engine having resolved the problems in time for the French Grand Prix.

Force India is expected to confirm whether Perez will need any engine component part changes during the build-up to this week’s Austrian Grand Prix which acts as the second race of F1’s triple-header.