Consumer Reports panned the high technology Fisker Karma after testing the $107,850 luxury plug-in hybrid.
The magazine said the sleek-looking car suffers from significant reliability problems and doesn't compare well to other luxury sports cars, such as the Porsche Panamera.
The Fisker runs on electricity for about 70 kilometres. A small gasoline engine kicks in and extends the range once the car's battery charge runs out.
Only a few thousand have been sold, but the car has already attracted attention for its styling. Celebrities Leonardo DiCaprio and Justin Bieber both drive Karmas.
"Despite the car's huge dimensions, it's very cramped inside. The overcomplicated controls are frustrating and it's hard to see out," said Jake Fisher, director of Consumer Reports Auto Test Center.
"When it's running, the gasoline engine has an unrefined roar. And the Karma's heavy weight affects agility and performance."
Fisher said he found the Karma's ride, handling and braking performance "sound" and noted the car has first-class interior materials, but concluded "the Karma's problems outweighed the good."
The review said that the Karma's "badly designed touch-screen system makes the dash controls an ergonomic disaster."
The car was purchased by the magazine for its test.
Fisker, which is based in Anaheim, California, and assembles the vehicle in Finland, defended the Karma.
"Since its launch in December 2011, the award winning Fisker Karma has defined a new automotive segment of luxury electric vehicles," the company said in a statement.
It noted that the vehicle has won praise from other publications.
Automobile magazine named the Karma its Design of the Year and Time magazine listed the vehicle as one of its 50 Best Inventions, Fisker said.
Fisker said it is working to improve responsiveness and functionality of the Karma's touch-screen controls.
The company has struggled recently with stalled development, missed deadlines and employee layoffs.
