Reigning World Champion Lewis Hamilton was left to rue a 'de-rating' car during the European Grand Prix, which left him with less electrical deployment than usual.
Hamilton started from 10th after crashing during qualifying but recovered to fifth when he encountered the problem.
Hamilton asked for advice via the team radio but under the regulations his engineer was not permitted to offer assistance, much to the Briton's annoyance.
Hamilton maintained fifth for the remainder of the race but slipped 24 points behind Nico Rosberg after his team-mate claimed victory.
"[I had an] engine problem, not sure what it was, with eight laps to go it fixed itself, felt like I was driving without the ERS pack," he explained.
"As far as I’m aware I was not in the wrong setting, I hadn’t changed anything, I’m sure we’ll find out afterwards.
"I can’t imagine what it is but I was driving without the ERS pack so had no boost for pretty much the whole race."
Hamilton was nonetheless positive over his prospects ahead of the next round in Austria.
"I've definitely had better seasons but [there's] still a long way to go and I will give it everything I can to keep battling and hope there’s less and less mistakes going forwards," he concluded.