Mercedes feeling more 'robust' about PU reliability issues

Mercedes boss Toto Wolff says the German outfit's engine reliability issues have now faded while its confidence on reaching the end of the season without incurring another grid penalty has increased.

Reliability concerns that emerged in the back half of the season prompted Mercedes to take pre-emptive action at several venues. Valtteri Bottas has so far been the recipient of six Internal Combustion Engines, three of which were beyond the authorized limit and thus led to three grid demotions for the Finn.

The concerns also extended to its customer teams, Williams, McLaren and Aston Martin which also underwent engine changes. In Mexico, Lance Stroll has been assigned a new unit that will send the Canadian to the back of the grid on Sunday.

But Mercedes' greatest concern was the possibility of championship contender Lewis Hamilton being forced to take a fresh engine and suffer the pain of grid drop.

However, Wolff believes that probability has now largely subsided.

"I think we're feeling more robust about one particular issue that seems to be solved," he said, noting how difficult it has become to recover from an engine change and grid penalty.

"I think it's never right to take a penalty, because these days it's so difficult to overtake.

"You can see that Valtteri was absolutely dominant in Turkey, but [in the USA] you just get stuck in traffic with the penalty.

"So we're taking it on the fly. We're deciding, do we need the penalty or are we not needing a penalty? And here certainly we won't take one.

"And maybe we don't need any until the end of the season. That is really something that is being discussed."

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Wolff acknowledged that Mercedes hasn't been able to find the sweet spot for its W12 in Mexico City, but the Austrian believes its engine is performing better than in previous years at the high-altitude Autodromo Hermanos Rodriguez venue.

"It was never such a happy place for us in terms of car performance, although we love Mexico because we're so welcome," said Wolff.

"We don't seem to find the sweet spot and so we were chasing various directions [in practice].

"On a positive note, our engine is performing well. There was a little bit of a gap in the years before, and that's fine.

"I think for us, it’s about doing the best possible job. But maybe that is difficult with Max's performance."

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