How the Tesla Model S snagged a higher reliability rating from Consumer Reports

Although the Tesla (TSLA) brand did not fare so well in Consumer Reports' most recent annual reliability survey, there was one bright spot: the Model S.

Tesla's low overall ranking owed a lot to issues with its Model X crossover , such as problems with its falcon-wing doors. But the Model S managed to improve this year — it now has an "average" rating, and Consumer Reports is recommending people buy the car.

Consumer Reports had given the Model S high scores on metrics such as road tests and performance, but had held back a recommendation due to reliability concerns, said Jake Fisher, Consumer Reports' director of automotive testing, in an interview with CNBC.

"In terms of any new or redesigned vehicles, we often see a tumble on reliability," Fisher said. "As the years go by, we always see reliability continue to improve" as companies work out bugs and design issues.

"The fact that the Tesla Model S is average at all, is impressive, considering the short life of this company, when you have automakers such as Fiat Chrysler (FCA-IT) unable to make very conventional cars reliable, the fact that the Tesla Model S is average is a very impressive feat."