2. Renault reliability
Another manufacturer that was having troubles with engine reliability was Renault. Ever since the start of the V6 hybrid turbo era, Renault has suffered problems second only to Honda. It was rather ironic as Renault was the major voice to demand a shift to V6 engines. When F1 did shift to these engines Renault was neither fast nor reliable.
Over the course of 3 years Renault did progress and by the end of 2016, their prime customer Red Bull was challenging for race wins. Coming into 2017, major pace and reliability progress was expected from Renault.
But the French marquee started once again with a stumble. Facing troubles in the winter testing, the engine maker had to switch back to last year specification of the ERS while work on the new specification continued to be introduced later. But Renault never got around to that.
Reliability was so poor for Renault that they had to scrap their plan of introducing performance upgrades altogether and switch focus to improving reliability. Yet out of the 6 cars on the grid that ran the Renault engine, at least 1 car suffered an engine related issue in every race.
Twice Hulkenberg suffered DNF while running in podium contention and on numerous other occasions the team lost valuable points. Jolyon Palmer, on the other hand, couldn’t even start his home grand prix because his engine blew up on the formation lap.
Renault’s reliability was one of the biggest if not the biggest disappointing Formula 1 moments of the season.