Electric cars have always been thought to be more reliable than gasoline or diesel-powered vehicles; after all, EVs have fewer moving parts, as well as less volatile liquids to carry around. However, a new study shows that electric cars may not be more reliable than ICE vehicles after all.

A new survey by UK consumer group Which?, as reported by Mail Online, reveals traditional gasoline or diesel-powered vehicle owners report fewer problems within the first four years of ownership than electric vehicle owners.

Which? surveyed 48,000 people about the vehicles they drive, which included 2,184 electric vehicles out of nearly 57,000. Thirty nine percent of electric vehicle owners reported a problem within the first four years of ownership, compared to just 19 percent of gasoline car owners, and 29 percent for diesel car owners.

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Not only do electric cars tend to be less reliable, the requirement to repair the problem usually takes them off the street for longer than a traditional ICE car. The most common problems occurred with the software, which took up to five days to repair, compared with a three-day repair for gasoline cars, and four days for diesels.

The least reliable of all the electric vehicle brands was Tesla, with 39 percent of owners recording at least one fault within 4 years of ownership, and 5 percent of problems included breakdowns or failures to start.

On the other end of the scale was Kia with its e-Niro, with only 6 percent of owners reporting a fault, and only 1 percent of owners reporting breakdowns or failures to start.

“We know that drivers are keen to make the move to more environmentally-friendly cars but it is vital that they are getting a quality product,” said Which? home products and services editor Lisa Barber. “With EVs in particular, our research shows a premium price tag does not necessarily mean a reliable vehicle, so we would always encourage drivers to do their research ahead of such a significant purchase to see which cars and brands they can trust.”

Granted, electric vehicles are still a fairly new product in the automotive world, but we’ll likely see increased reliability as the technology develops further.