Mercedes has confirmed the cause of Lewis Hamilton’s power unit issue in the closing stages of the Brazilian Grand Prix, with a full review set to take place following Friday’s practice running in Abu Dhabi.

Hamilton took his 10th victory of the season at Interlagos two weeks ago, but concerns were sparked in the closing stages of the race due to an apparent power unit problem.

Mercedes F1 boss Toto Wolff revealed Hamilton’s engine was one lap away from failing at one stage, prompting the team to make a number of setting changes.

“The problem in Brazil was caused by a failure in the variable inlet system that caused unstable combustion,” a Mercedes spokesman confirmed on Friday after the start of practice in Abu Dhabi.

“Engine settings were changed to contain the risk of failure/maximise performance during the race.”

Hamilton will use the same power unit for Friday’s practice running in Abu Dhabi to give Mercedes the chance to review it and consider whether it can be used for the rest of the race weekend.

“We have made hardware changes outside the sealed perimeter and we are running that engine (PU3) today,” Mercedes said.

“Data will be reviewed after FP2 to make sure all is OK."