Trouble-free day still leaves McLaren-Honda exposed

McLaren and Stoffel Vandoorne's test day was spared any drama which in itself should be hailed as a major event following the team's dismal reliability and performance to date.

While Oliver Turvey managed only 17 laps yesterday, Vandoorne clocked in with 82 laps, more than his total amount of race laps this year.

But team boss Eric Boullier insists that the trouble-free day only complicates Honda's task of getting to the bottom of its MGU-H problem which can pop up at anytime, without warning.

"It's very difficult to understand what's going on," he contested.

"We obviously changed the MGU-H four times and yesterday morning, two laps, MGU-H gone, changed the engine, did 17 laps yesterday.

"This morning we had a small alert but we couldn't find anything wrong physically on the car and then since then we've run faultlessly, without any problems.

"So I think it's going to be complicated for Honda to understand what's wrong, it could maybe be coming from some batch problems.

"I don't believe it is a car build problem but we can't find what's wrong... We can do two laps or we can do two days."

Bottas wraps up Bahrain in-season test on top

Regardless, Vandoorne's time behind the wheel of the MCL32 was still put to good use with regard to advancing knowledged and collecting data.

"We had good days last year as well I think. But today we are following the test plan and a lot of information has been understood and solutions tested on the car.

"So a very good test in terms of data and results."

GALLERY: All the action from the Day 2 in-season testing at Bahrain

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Phillip van Osten

Motor racing was a backdrop from the outset in Phillip van Osten's life. Born in Southern California, Phillip grew up with the sights and sounds of fast cars thanks to his father, Dick van Osten, an editor and writer for Auto Speed and Sport and Motor Trend. Phillip's passion for racing grew even more when his family moved to Europe and he became acquainted with the extraordinary world of Grand Prix racing. He was an early contributor to the monthly French F1i Magazine, often providing a historic or business perspective on Formula 1's affairs. In 2012, he co-authored along with fellow journalist Pierre Van Vliet the English-language adaptation of a limited edition book devoted to the great Belgian driver Jacky Ickx. He also authored "The American Legacy in Formula 1", a book which recounts the trials and tribulations of American drivers in Grand Prix racing. Phillip is also a commentator for Belgian broadcaster Be.TV for the US Indycar series.